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Bulletin No. 8 

U. S. DEPARTMENT OF AGRICULTURE. 



BUREAU OF ANIMAL INDUSTRY. 



ul - 



if 



INVESTIGATIONS 



CONCERNING 



NFECTIOUS DISEASES AMONG POULTRY. 



THEOBALD SMITH, Ph. B., M. D., and VERANUS A. MOORE, B. S., M. D., 



UNDER THE DIRECTION OF 



Dr. D. E. SALMON, 

CHIEF OF THE BUREAU OF ANIMAL INDUSTRY. 




WASHINGTON: 

GOVERNMENT PRINTING OFFICE. 
1895. 



LETTER OF TRANSMITTAL. 



U. 8. Department of Agriculture, 

Bureau of Animal Industry, 

Washington,, D. C, June 29, 1895. 
Sir : I have the honor to transmit herewith a report of Drs. Theo- 
bald Smith and Veranus A. Moore concerning investigations of certain 
nfectious diseases of poultry. This subject is one of great interest and 
mportance to most people of this country who are engaged in agricul- 
;uial occupations, and particularly to all who make a specialty of some 
jranch of the poultry industry. There are a vast number of our citi- 
:eus engaged m the production of poultry and eggs, either for their 
)wn use or for sale, and most of these at one time or another suffer 
osses and have their operations interfered with by outbreaks of infec- 
ious diseases. Such diseases are as destructive with birds as with 
>ther kinds of animals, and until recently they nave received little 
lystematic study from competent scientific men. 

The investigations, of which an account is presented in this bulletin, 
»pen up a new field for scientific inquiry. While the work which has 
>een accomplished is but the first step, it reveals how little has been 
blown and how much is to be learned in regard to the diseases of 
)irds. The greater part of the losses from infectious diseases in the 
>oultry yard may probably be prevented by the intelligent application 
>f proper sanitary measures. Until the nature of these diseases is 
learly understood, however, it is impossible to intelligently formulate 
preventive measures or to prescribe successful methods of treatment. 

The financial investment in domesticated birds is of such magnitude, 
md the products are marketed in such vast quantities, and are so 
isseutial to the well being of every citizen that the problems affecting 
his industry are deserving of the most careful study and investi^a- 
ion. The researches herein reported have been made in i he hope and 
expectation that they would be continued until practical means of pre- 
senting the common infectious diseases are placed within the reach of 
II engaged in the poultry industry. 
Very respectfully, 

D. E. Salmon, 
Chief of Jin rea a of Animal Industry. 
Hon. J. Sterling Morton, 

Secretary of Agriculture. 

§ 



LETTER OF SUBMITTAL. 



U. S. Department of Agriculture, 

Bureau of Animal Industry, 

Washington, D. C, April 2, 1895. 
Sir : I have the honor to submit herewith some preliminary studies 
of infectious diseases among poultry, including fowls, turkeys, and 
pigeons. Though these studies have not yet reached that state which 
permits us to recommend any well-defined preventive or curative meas- 
ures, it is to be hoped that they will give those immediately interested 
a better insight into the nature of some of these diseases, besides fur- 
nishing investigators throughout our country a more secure basis for 
further experimentation. 

Very respectfully, 

Theobald Smith, 

Chief of Division of Pathology. 
Dr. D. E. Salmon, 

Chief of Bureau of Animal Industry. 
4 



TABLE OF CONTENTS. 



Page. 

An Infectjous Disease among Turkeys Caused by Protozoa (infectious 

entero-hepatitis). By Theobald Smith 7 

Special characters of the disease 8 

The micro-organism {Amoeba meleagridia n. sp., 1895) 15 

The relation of bacteria to the disease 21 

The relation of this disease to certain other diseases of poultry 22 

General conclusions 24 

Appendix 27 

A Preliminary Investigation of Diphtheria in Fowls. By Veranus A. 

Moore 39 

Outbreaks 42 

Bacteria associated with the lesions 53 

Description of the nonmotile bacillus 5G 

Prevention and treatment 58 

The relation of diphtheria in fowls to public health 60 

Conclusions 61 

A Study of a Bacillus Obtained from three Outbreaks of Fowl 

Cholera. By Veranus A. Moore 63 

History of the outbreaks 64 

Description of the bacillus 65 

The nature of the inoculation disease 67 

On a Pathogenic Bacillus of the Hog-Cholera Group Associated with 

a Fatal Disease in Pigeons. By Veranus A. Moore 71 

History of the disease 71 

Description of the bacillus 73 

5 



LIST OF ILLUSTRATIONS. 



Facing 
page. 

Plate I. Photographic reproduction of the caecum ami the spleen from a 

turkey affected with the protozoan disease 78 

II. Drawings of normal and diseased caeca and of tbe spots on the liver. 80 

III. Recent and advanced stages of the liver disease 82 

IV. Microscopic appearance of the diseased ca'cum and liver with the 

microparasites shown 84 

V. Drawings showing microparasites, giant cells, and ilagellatesfrom 

the blood 86 

VI. Drawings showing the diphtheritic lesions in the mouth and on 

the cornea of a fowl 88 



INVESTIGATIONS CONCERNING INFECTIOUS DISEASES AMONG 

POULTRY. 



AN INFECTIOUS DISEASE AMONG TURKEYS CAUSED BY PROTOZOA (INFECTIOUS 

ENTERO-HEPATITIS). 



By Theobald Smith. 

[Platen I to V, inclusive.] 

In the full of 1S93 the writer received from Mr. Cushman, of the 
Rhode Island Experiment Station, the organs of an adult turkey in 
which the liver and the casca were very extensively destroyed by a 
peculiar disease. A second case was sent by Mr. Cushman in April 
ot 1894, in which the same disease was recognized. In June of 1894 
the writer found the same affection in a very young turkey in western 
Massachusetts. The changes induced by this affection were so pecul- 
iar and yet so uniform in these three cases that a specific infectious 
disease could not but suggest itself on even superficial examination. 
A careful study of this material convinced the writer that the cause of 
this disease was a protozoan parasite not hitherto recognized. It was, 
therefore, deemed best to investigate the disease more thoroughly, and 
for this purpose the writer spent three weeks at the Ehode Island Sta- 
tion during the mouth of August. The turkeys were obtained by vol- 
untary contribution and by purchase, mostly from localities within 
5 to 10 miles of Kingston, R. I. Some came from a greater distance. 
In this work I was greatly assisted by Mr. Cushman, in charge of the 
poultry work, and by Professor Flagg, director of the station. The 
chemical apparatus of the station was placed at my disposal by 
Professor Wheeler. 

With the aid of the apparatus brought from Washington and that 
on hand I was enabled to make a careful examination of about 50 tur- 
keys. Of these, IS were affected with the specific protozoan disease, 
and many of the rest were affected with other diseases, briefly referred 
to under each case. 

The short space of time which could be devoted to this subject did 
not enable the writer to do more than to make a preliminary study 
of the disease and its cause and to collect material for further study. 

7 



8 INFECTIOUS DISEASES AMONG POULTRY. 

Now that a firm basis for the investigation of the practical problems 
has been secured, it is to be hoped that the investigation will be prose- 
cuted during the coming summer, both at the experiment station of 
the Bureau and elsewhere. The publication of the work thus far done 
will also enable the various experiment stations to make observations 
on the communicability of the disease and on means for its eradication. 

The external appearances of the turkeys affected with the disease do 
not seem to be constant, and this is not to be wondered at in view of 
the varying intensity of the changes found in the internal organs. In 
Rhode Island the disease is known as " blackhead," owing to certain 
peculiar discolorations which take place at the height of the disease. 
While it might be well to retain this as a popular name, we do not 
believe that all cases of blackhead have the specific disease herein 
described, nor do all turkeys affected with this disease manifest the 
appearances of blackhead. More extended study is needed before we 
may rely upon symptoms as a means of recognizing this disease during 
life, especially as there are several other affections of turkeys quite 
distinct from this concerning which there exists as yet very little defi- 
nite information. 

As brought out more fully further on, the disease may be recognized 
by anyone who has made himself familiar with the salient facts in this 
article by an examination of the organs of the diseased turkey after 
death. 

Among the symptoms which may be expected to appear sooner or 
later, diarrhea probably occupies a prominent place. The disease of the 
caeca is responsible for this. Yet we may have diarrhea with at least 
one other disease of the creca, and the presence of tapeworms may also 
cause this disturbance. Emaciation was not constantly present in the 
cases dissected by me. As it may accompany other wasting diseases, it 
can not be depended upon as a sign of this affection. 

Leaving this part of the subject we shall turn to those characters of 
which the investigations have given some definite information. 

SPECIAL CHARACTERS OF THE DISEASE. 

The disease seems to attack turkeys when quite young. In early 
June I found a turkey about 3 weeks old (No. 3) in which the dis- 
ease had already made considerable progress. It seems, moreover, as 
if the disease were contracted only by the young, because in the 
examination of turkeys of different ages the oldest showed lesions of 
the longest standing; that is, such as had undergone the most exten- 
sive transformation. In general it may be said that the age of the 
turkey corresponded with the age of the disease process. The most 
serious and extensive destruction of tissue was noticed in the turkeys 
in fall. In midsummer the disease was making most progress; that is, 
it was freshest and the microparasites present in great numbers. It is 
probable that the delicate tissues of the young are best adapted for 



SPECIAL CHARACTER OF THE DISEASE. 9 

the temporary habitat and rapid multiplication of this parasite. In 
this regard it simply follows the rule observed by large numbers of 
parasites, whose most destructive action is visited upon the young. 

The primary seat of the disease are the cseca. From these the liver 
is invaded. Other organs are not attacked. 

The caeca of the turkey in the normal condition are represented by 
two blind tubes opening into the intestine at a point about 6 inches 
from the cloaca (PI. II, tig. 1; PL I, fig. 1). They are directed toward 
the head, the blind end being nearer the gizzard than the opening into 
the intestine. They lie on either side of the latter, closely bound to it 
by mesenteries. The tips only are free. The length of the caeca varies 
according to age. In turkeys 3 months old they are about 8 inches 
long, while in those nearly a year old they are from 10 to 12 inches 
long. 1 

The caeca are of nearly the same diameter as the intestine. When 
only slightly filled they are 4 to 5 mm. (one-sixth inch) in diameter. 
They may, however, be distended with feces to three times this diam- 
eter. The structure of the walls seems to be identical with that of the 
intestine to which they are attached. The communication between 
caeca and intestine is somewhat contracted. Near it in each tube there 
is a convex elevation about one-half of an inch long which is composed 
of lymphatic tissue. Its surface is usually deeply pigmented. Other 
lymphoid structures are represented by small elevations only three- 
sixteenths of an inch in diameter, usually pigmented and scattered 
sparsely over the mucous membrane. The mucosa itself is folded in 
longitudinal ridges, which are frequently pigmented. 

The caeca usually contain feces in greater or less abundance which 
are pasty, homogeneous in texture, and greenish in color. Under the 
microscope they appear to be composed mainly of bacteria. When the 
feces have a softer consistency numerous flagellates of several distinct 
forms may be detected in active motion in the feces of the recently 
killed bird. They appear to increase in number with the increase in 
the watery constituents of the feces. 

Coccidia have also been detected. They were present in No. 3 and 
in another young turkey of the same flock which died from some 
unknown cause. In the caecal contents of No. 17, which was free from 
disease, similar bodies were found, the largest measuring 32 by 18 //. 
They were in form and structure like Coccidium oviforme of the rabbit's 
liver, and perhaps identical with the form seen in the caeca of fowls by 
Eivolta and Silvestrini and named C. tenellum by Eailliet and Lucet. 2 
It is very improbable that these bodies stand in any genetic relation to 
the true microparasites of the disease herein described. 

The lesions of the caeca are in substance a thickening of the wall, 

1 The length of the intestine from gizzard to opening into ca?ea is about 5 feet for 
turkeys 3 months old and 8 feet for those nearly a year old. 
2 Zoologie Medicale, second edition. 



10 INFECTIOUS DISEASES AMONG POULTRY. 

followed in most cases by a destruction of the epithelium and deeper 
portions of the mucous membrane. This destruction results in the 
outpouring of a coagulable fluid into the tube (PL I, fig. 1; PI. II, figs. 
2, 3, and 4). The thickening of the wall may vary considerably in 
extent from case to case. It may be uniform over the greater portion 
of the tube or it may be limited to circumscribed patches. The com- 
monest seat of these lesions is near the bliud end of the tube, where it 
evidently starts and from whence it spreads to other portions. Not 
infrequently only one caecum was found diseased, the other normal. 
This exemption was not due to mildness of the attack, for the other 
caecum may, in such cases, be the seat of very extensive changes. Thus 
of 18 cases only 11 had both caeca involved. 

The affection of the caecum is due primarily to the multiplication of 
the microorganism to be described below, within the walls of the 
caecum. The multiplication may take place chiefly in the mucous mem- 
brane, or in the submucous tissue, or it may, though rarely, extend into 
the muscular coat. The thickening of the wall is the result of several 
processes — the multiplication of the parasites, the increase of the normal 
tissue elements, and later on the accumulation of masses of small cells 
and some giant cells. 

In the early stages of the invasion the adenoid tissue between the 
tubules and in the submucosa becomes greatly increased, owing to the 
presence of large numbers of microparasites of round or slightly oval 
outline and from 6 to 10 jj. in diameter which stimulate the proliferation 
of the tissue cells. Numerous mitoses have been seen in this stage. 
The parasites seem to occupy the meshes of the adenoid tissue either 
singly or in groups or nests (PI. IV, figs. 1, 2). In these meshes they 
are soon enveloped in cells acting as phagocytes, so that the appearance 
of an intracellular habitat of the parasites is suggested, which is, how- 
ever, only an appearance and not demonstrated by further study. 

The presence of the parasites in this reticulum probably stimulates 
also the accumulation of lymph cells within the spaces, in virtue of 
which the mucous membrane is thickened. In this early stage of inva- 
sion the epithelium, both of the tubules and of the surface, remains 
unaffected. The parasites do not invade the epithelium at anytime. 

As the disease progresses there is a continued increase in the cellu- 
lar elements of the mucous and submucous coats and a gradual invasion 
of the muscular coats. Here the bundles of fibers of the circular coat 
are thrust apart by masses of cells, so that this coat also becomes 
greatly thickened. The inflammation finally extends to the serous 
covering, where the blood vessels become greatly dilated and give the 
cajcum a congested appearance. In cases of ordinary severity the wall 
of the caecum, not more than 0.2 to 0.5 mm. (one one hundred and 
twenty-fifth to one-fiftieth inch) thick normally, according to distention, 
becomes 2 to 3 mm. (one-twelfth to one-eighth inch) thick. 



SPECIAL CHARACTER OF THE DISEASE. 11 

With the progress of the disease the mucous membrane may be shed 
and a coagulable fluid poured out into the caecum. In some cases it 
appears in isolated masses, which adhere to certain spots of the mucous 
membrane. In others, this exudate tills the entire tube with a yellowish- 
white mold (PI. II, tigs. 2, 3). This is built up in concentric layers, 
and consists of a mixture of blood corpuscles, fibrin, and masses of 
small round cells, in variable proportion. 

In the further progress of the local disease it is not improbable that 
bacteria are also concerned. The exudate contains immense numbers 
of them and the denuded mucosa furnishes a favorable place of entry. 
It is otherwise difficult to explain the continued increase in thickness 
of the walls of the caecum after the mucous membrane has been shed. 
This continued increase in thickness is due to an extensive infiltration 
of small round cells and the presence of some giant cells. Parasites 
in this advanced stage are scarce, ami usually recognizable only as 
vacuole-like bodies within the giant cells. 

The thickening of the wall is associated in some cases with an exten- 
sion of the inflammation to the contiguous wall of the intestine, which is 
thereby firmly attached to the caecum. Yellowish exudates are some- 
times found outside of the diseased caecum on its serous covering and 
they bind it inextricably to the other caecum or to the intestine or at- 
tach it to the abdominal wall. In these stages the inicroparasite is not 
found. It seems to have done its work by destroying the mucous 
membrane and to have left the field for miscellaneous bacteria. 

In no case were oilier regions of the digestive tract affected. Though 
the inflammation set up in the affected caecum may have extended 
through the wall to the contiguous intestine and caused the formation of 
a large amount of neoplastic tissue between the adjoining tubes, the 
disease did not invade the submucous or mucous membrane and the 
specific parasites were absent. 

Associated with this peculiar disease of the caeca is a more or less 
serious disease of the liver. In the 18 cases of protozoan disease the 
liver was very extensively diseased in 10. In two cases only small 
sclerotic foci were present and in these the lesions of the caeca were 
evidently at a standstill, or in a condition of active cicatrization. The 
affection of the liver is in tact a valuable means of recognizing this 
disease, for wherever it is present we may safely infer that we have 
the protozoan disease before us. The reverse is, of course, not neces- 
sarily true. The disease of the caeca may be so restricted that the 
secondary liver disease does not appear. Nevertheless, the value of the 
liver affection is indicated by the fact that in the few cases of c;ecal 
affection in which the disease was of a different character no changes 
in the liver were manifest (Nos. 25, 41). 

The appearance of the liver in the average case of this disease is 
very striking. The organ itself is enlarged in proportion to the amount 
of tissue involved. Twice the normal size is probably near the truth, 



12 INFECTIOUS DISEASES AMONG POULTRY. 

although but one was weighed to accurately determine this point. In 
this case (No. 52) the liver weighed 10.7 ounces. 

Over the surface of the organ are distributed roundish, discolored 
spots, distinctly demarcated from the surrounding tissue. These spots 
vary much in numbers, in size, and in appearance. They may be dis- 
tributed uniformly over the whole surface of the liver or they may be 
limited in number to a few. They vary from 3 to 15 mm. (one-eighth to 
two-thirds inch) in diameter. Inasmuch as a detailed description of 
the different cases examined is given in the appendix, to which the 
reader is referred, only a general description will be attempted here. 

In endeavoring to group these spots according to their general appear- 
ance we find several types, which, as will be seen below, correspond to 
different conditions of the diseased tissue. We have in the early most 
active disease process, spots like those photographed and figured in Pis. 
I and II. They are sharply defined circular areas of a lemon yellow or an 
ocher yellow color. A careful scrutiny shows that the spot is not homo- 
geneous in structure, but made up of a delicate network of yellow, as 
shown in the plates. This yellow substance represents dead tissue. 

In another class of spots we have in place of the yellow meshwork an 
entirely different appearance. The spot is of a mottled brownish color 
and contrasts only slightly from the surrounding liver tissue by its 
darker color. It may contain a central yellow nucleus of dead tissue and 
a narrow outer border of the same character, or the border may be a 
dark brownish circular line. The entire spot has an indistinct appear- 
ance and is flattened or even slightly depressed below the surface. Jn 
some cases the spots assume still another aspect. They are uniformly 
whitish and shade off somewhat gradually into the surrounding tissue. 

If sections be made of the affected organ it will be noticed that these 
surface spots represent masses of liver tissue in the same condition. 
The spots are simply the places where these disease foci intersect the 
surface. Some are found deeply embedded in the liver tissue, and 
therefore not visible on the surface. The lesion of the liver is thus 
represented by few or many foci of disease having in general a spheri- 
cal form and appearing on the surface of the organ as round spots (PI. 
Ill, fig. 1). Occasionally the lesions become more extensive and the 
death of large portions of liver tissue follows. This is well shown in 
fig. 2 of PI. Ill, where a large volume of liver tissue is transformed into 
a yellow cheesy substance. 

The changes in the liver are most easily explained by assuming that 
the microparasites are conveyed by the blood directly from the diseased 
cseca into the liver and there deposited in different places, where they 
begin to multiply and spread in all directions, thereby forming the 
spherical foci of disease which appear as circles on the surface of the 
liver. This theory is borne out by the results of the microscopic exam- 
ination. 



SPECIAL CHARACTER OF THE DISEASE. 13 

In sections of hardened tissue from the liver in which the disease has 
but recently begun the affected regions are invaded by large numbers 
of protozoa, which occupy a kind of reticulum formed probably from the 
connective tissue stroma. The liver cells have partially or wholly dis- 
appeared from these foci. The parasites occupy the meshes of the tis- 
sue either singly or in groups. The reticulum is provided with a small 
number of nuclei, some of which are closely applied to and curved 
partly around the parasite. The blood vessels are usually much dilated 
and filled with red corpuscles. 

The yellow masses observed with the naked eye in the surface spots 
in many cases are Shown to be patches of an amorphous substance 
which takes nuclear stains very feebly, the aniline colors not at all. It 
may be described as a coarse network in the meshes of which small cells, 
and very rarely parasites, are seen. This substance I assume to be the 
result of coagulation necrosis of the liver cells by which they have lost 
their nuclei and have become fused into a formless mass. I at first 
was inclined to look upon it as fibrinous in character, but the discovery 
of transitional stages confirms the view that it is made up of dead liver 
cells. It is probable that the plugging of blood vessels in the liver by 
parasites carried from the caecum is tbe cause of the necrosis, since 
such plugs or thrombi are not uncommon in sectious of the diseased 
spots. 

With the appearance of the microparasites reactive changes begin 
at once which complicate the process. We have at the outset an 
active multiplication of the microparasites which take the place of the 
original liver tissue, and a process of coagulation necrosis going on at 
the same time. Soon multinucleated (or giant) cells appear which not 
only take in the microparasites but which are also engaged in remov- 
ing dead tissue. At least their collection in groups around and within 
the necrotic areas lead us to assume this. Not infrequently they are 
grouped around what appears to be a plugged vessel, or else they 
occupy the lumen of the vessel itself. The presence of round or oval 
vacuoles within these large cells indicates that parasites have been 
taken up (PI. V, fig. 3). 

In still older cases the diseased spots are found more or less filled 
with small round cells which may have passed into the dead regions 
from the blood vessels. In all cases the latter are more or less enlarged, 
and they seem to encroach upon the liver tissue, thus filling in part 
the void produced by the cell death and giving the surface of the liver 
a brownish mottled appearance wherever the disease spots are. 

The processes of advancing disease and necrosis or death of tissue 
on the one hand, of repair on the other, seem to go on side by side, now 
one now the other predominating. Of the process of repair case 16 is 
a very good illustration. In this bird the liver tissue was undergoing 
sclerosis associated with the true healing process, which is referred to 
more in detail in the appendix. 



14 [NFECTIOUS DISEASES AMONG POULTRY. 

Besides the lesions directly due to the mioroparasites in the cseca and 
in the liver, there were aochanges observed to indicate thai the parasite 
was multiplying in other parts of the body. Even where the disease 
was extending locally from caecum to adjoining intestine, the process 
was not due to any advance or invasion of the parasites themselves. 

Regularly recurring changes in other organs duo indirectly to the 

• lest ruction of liver tissue, and to tho loss of the cava as important 
aids in the process of absorption were not manifest. 

The blood of many of the eases was examined before the bird was 
killed in older to detect any existing blood infection. No disease of 
tlic blood was observed, however, excepting in No?l(>, in which a pro- 
nounced leucocytosis was present. In this case the disease was disap- 
pearing and the liver undergoing sclerosis, as stated above, in a 
small number of cast's, some diseased, some healthy (Nos. 5, f>, L2, 15, 
and 33) flagellates were detected in variable numbers. They were 
evidently not related in any way to the protozoan disease. These 
bodies (PI. V. figs. 6 and 7) are spindle-shaped and made up of an oval, 
feebly granular, central body (nucleus) around which the cell body 
forms two lateral wings and two tapering extremities finely granular in 
structure. Motion was not detected at the temperature of the sur- 
rounding air. Higher temperatures were not applied. The nucleus of 
this flagellate is about 25 n long and (i // broad. The entire organism 

15 65 to 70 a long. When the blood is dried in thin films upon cover- 
glasses and stained, these bodies appear in many instances much 
broader than in the fresh condition. This would suggest that the 
organism may be a flattish body rolled up so as to bring the two lat- 
eral margins near together. 

The results of the examination of turkeys made thus far indicate that 
the disease may follow several courses: 

(1) After a certain period of disease regenerative processes begin 
which tend toward a permanent recovery. 

(L*) The disease may proceed so rapidly from the very start that the 
affected turkeys die early in life. 

(3) The disease may come to a standstill, but the amount of dead 
tissue in theea'ca and liver may be so great as to favor the entrance of 

bacteria which are responsible directly for the death of the bird late in 
the summer or fall. 

The direct action ol' the microparasites upon the body seems to lead 
to a mechanical destruction of tissue. In this respect they differ from 
most bacteria, which may combine a locally destructive process with a 
general poisoning ol' the body. The extensive destruction of liver 
tissue combined with the loss of the use of one or both caeca in the 
digestive process must of necessity lead eventually to weakness and 
emaciation. The feebler resistance of the atl'eeted animals was brought 
to our notice last summer by their speedy death after a long ride or a 
few days oi' confinement. 



THE MICROORGANISM. 15 

As regards the spontaneous cure of infected birds we may regard i 
as probable that only those in which the disease comes to a standstill 
before it has made much headway are likely to recover. In those in 
which much destruction of tissue has taken place complete recovery is 
impossible. The dead masses embedded in the caeca or the liver, or both, 
form a nidus for bacteria of certain kinds. These penetrate into the 
pleuroperitoueal cavity and there set up inflammation and finally lead 
to a general septic infection of the body. The immediate effect of the 
disease may thus be very slight at the outset and the symptoms develop 
slowly. The great increase in the size of the liver indicates a certain 
amount of compensation for those portions which have been destroyed. 

The effect of the disease on the flesh of turkeys killed in the early 
stages is not recognizable. In a few cases which died from a severe 
form of the disease the flesh had a mahogany color, probably due to 
retained biliary substances. 

THE MICROORGANISM. 

(Amaba meleagridis n. #p. 1S95.) 

In the 18 cases of this disease which came under observation either 
the liver or the ca^ca, or both organs, were examined microscopically in 
14. In these organs certain microorganisms were detected in all but 
one case and associated directly with the peculiar disease process 
already described. In those cases in which the disease was recent, or 
at its height, the parasites were very numerous in the affected tissues, 
while in those; in which the disease process was far advanced, and 
associated with degenerative or regenerative changes, the parasites 
were found with difficulty. These facts are summarized in the follow- 
ing table: 



16 



INFECTIOUS DISEASES AMONG POULTRY. 



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I 



THE MICROORGANISM, 17 

In the examination of the parasite within the tissues minute particles 
of the latter were crushed in iodized amniotic fluid or in normal salt 
solution. Sections were also made. Unfortunately, a freezing micro- 
tome was not at hand, nor any warm stage for determining- the effect of 
higher temperatures on these bodies. 

The most frequent appearance presented by the parasites under these 
circumstances was that of round homogeneous bodies with a sharply 
defined, single contoured outline (PI. V, fig. 1). Their appearance sug- 
gests that of the myelin bodies found in the cells of the pulmonary 
alveoli, not refrangent enough to represent oil globules, but too homo- 
geneous to represent the ordinary protoplasm. Within these bodies 
and situated somewhat eccentrically is a group of very minute granules, 
probably representing a nuclear structure. These forms were encoun- 
tered in those cases in which the parasites were found most abundant 
in sections of hardened material (Nos. 5, 24, 26) ; also in one case in 
which repair was evidently going ou (No. 16). They vary somewhat in 
size. In Nos. 5 and 16 those that were measured were 8 to 10 /z in 
diameter. In No. 26 they were 12 to 11 /< in diameter. In No. 34 some 
of the bodies were oval, having diameters of 12 and 15 /<, respectively. 
They are thus distinctly larger than the parasites within the tissues, 
which have undergone the hardening process. The latter are from 6 to 
10 j.i in diameter. This difference may be due to shrinkage, on the one 
hand, and on the other to a slight flattening of the bodies by pressure 
in the fresh preparations. These peculiar homogeneous bodies were 
found, as a rule, free in the crushed preparations, although occasionally 
giant cells were detected which contained a number of them. The cell 
nuclei of the giant cell were not visible in the fresh condition. Numer- 
ous coarse granules were embedded in its protoplasm, less frequently 
fat globules. 

Besides the homogeneous bodies, organisms of nearly the same size 
but with uniformly granular protoplasm were also found, chiefly within 
giant cells. These were not infrequently broken and rims or fragments 
of protoplasm were left attached to the parasite (PI. V, fig. 2). 

For the study of hardened material the tissues were removed in most 
cases immediately after the bird had been killed, and placed in one or 
more of the following fixing and hardening agents: 95 per cent alcohol, 
saturated solution of corrosive sublimate, Foa's solution (equal volumes 
of the preceding solution and a 5 per cent solution of bichromate of 
potash), Flemming's solution (undiluted). The tissues were fixed in the 
three last mentioned during one day, then washed in running water 
during another day and treated with ascending strengths of alcohol, 
according to the usually prescribed rules. The tissues were then passed 
through absolute alcohol and chloroform, infiltrated in paraffin, and the 
sections cut dry. Various staining reagents were employed, including 
Delafield's hematoxylin and eosin, alum carmine, Biondi's triple stain, 
saffranin, Gram and (Iram-Weigert's. stain. Of the fixing and hard- 
17897— No. 8- 2 



18 INFECTIOUS DISEASES AMONG POULTRY. 

ening agents I am unable to consider any one as superior to tue 
other in bringing out the parasites in the tissues when subsequently 
stained. By this I do not mean to infer that there was no preference 
when their action upon the tissues is considered, for here they mani- 
fested their respective peculiarities already well known. But the fact 
remains that now the one, now the other, tissue demonstrated the para- 
sites best. In general, hardening in corrosive sublimate and alcohol and 
staining in Delafield's hematoxylin and in eosin proved the most suc- 
cessful. The bodies were, however, brought out with other dyes, such as 
methylene-blue, with variable distinctness. 

The microparasites as found in sections of hardened tissue are spher- 
ical or slightly oval bodies from G to 10 fx in diameter. In sections 
stained with hematoxylin and eosin they have a homogeneous bluish- 
red tint, feebler than that of the tissue nuclei of the host. They are, 
however, distinctly seen, and the advantage of a more intense stain is 
questionable. In most of these bodies a minute, distinctly blue ring is 
seen situated centrally or somewhat eccentrically and representing the 
nucleus. This is about 2 // in diameter. With high powers a very minute 
(nucleolar?) point may be seen in some parasites within the nucleus. 
Other differentiations of structure were not noticed. 

The presence within the connective tissue spaces of parasites in 
groups of two or more individuals, as well as of single individuals, 
makes it highly probable that at least in the early stages of the disease 
there is active multiplication of these bodies. This appears to go on 
as a simple process of division, if we are to judge from the grouping 
within the tissues. The variation in the number of individuals com- 
posing such groups, as well as the absence of any common membrane 
inclosing each group, indicate at least that the multiplication is not an 
endogenous segmentation such as belongs to the sporozoa. 

This brings us to a consideration of the nature of these protozoa. 
Their simple structure would lead us to class them with the amoebae, of 
which one form is now known to produce a similar disease in the human 
subject (amoebic dysentery). Amoebae are also not uncommon inhabit- 
ants of the large intestine of man and certain animals. The peculiar 
homogeneous structure and rigid outline of the organisms before us as 
they appear when examined in tissues directly from recently killed 
animals may represent a kind of encystment in the presence of the 
adverse forces of the animal tissues. In the sharply defined vacuoles 
within the giant cells this rigid form seems to have left a permanent 
impression (PI. V, fig. 3). 

The relation which the parasite bears to the microparasites found in 
external tumors or warts (Molluscum contagiosum) of fowls, or to those 
flagellates which are associated with diphtheria in fowls, or finally to 
the diphtheria referred to in text-books as due to gregarinosis may be 
a very distant one. Yet, in the present state of our information con- 
cerning these parasites, it is worth while to be on our guard before 



THE MICROORGANISM. 19 

making positive assertions, and leave it to future work to decide if any 
relationship exists. 1 

We are naturally led, in a consideration of this microorganism, to 
inquire what relation it bears to the tissue cells of the host. Is it an 
intracellular parasite during- any portion of its parasitic existence? 
The evidence brought forward here would lead me to state that it lives 
in the interstices and lymph spaces of the tissue, but not within cells. 
This seems certainly true of the caecum. In the liver the liver cells 
seem to become necrotic or else, disappear so rapidly that it is impos- 
sible to determine just where the parasites begin to multiply. They do 
not live within the blood vessels, as they are not found within them 
excepting perhaps in a thrombosed vessel. They must, therefore, 
occupy the place of the liver cells. It is probable that they begin to 
multiply in the connective tissue adjoining the bloodvessel, and simply 
crowd out the liver cells, leaving the connective tissue stroma of the 
lobules in whose meshes they are found. 

Their presence within giant cells i-s seen in almost every infected 
organ subject to examination. In teased preparations of the fresh tis- 
sues they are frequently found with remnants of the inclosing cells 
still attached. This intracellular condition is, however, a purely pas- 
sive one so far as the parasite is concerned. 

The fate of the microparasite within the tissues of the host seems to 
tend toward destruction. Both the death of the tissue itself and the 
repair seem to lead to the disappearance of the parasites. In most 
cases there may be seen in the same section a partial dissolution of 
some of the bodies, while others are still in good preservation. Evi- 
dently their life within the tissues is not very long. The attack upon 
them by large giant cells in the later stages of the disease has already 
been mentioned. 

A discharge of the mieroparasites which escape destruction probably 
takes place from the walls of the caecum, when these break down, into 
the contents, in which they are carried outward. A similar discharge 
may take place from the liver through the bile ducts into the intestine. 
Another way of dissemination would be in the death of the diseased 
turkey and the dissolution of its body whereby the organisms are set 
free. Speculations in this direction are, however, of little value until 
experiment shall have determined whether turkeys are infected directly 
from sick turkeys, from healthy, immune or recovered turkeys, in whose 
ca-ca the parasite may perhaps vegetate indefinitely, or from some 
external source. 

The close analogy existing between this disease and that of amcpbic 
dysentery in the human being deserves at least a brief statement in 
these pages. The occurrence of amoebae in intestinal affections of man 
was noticed as far back as 1875 by Losch. Since that date it has been 

1 The presence of numerous flagellates in the caeca of healthy turkeys has already 
been poiuted out ou page 9. 



20 INFECTIOUS DISEASES AMONG POULTRY. 

the subject of many investigations. 1 Two of the more exhaustive 
investigations which have appeared are those of Councilman and 
Lafleur 2 and of Kruse and Pasquale. 3 

The points of analogy between the avian and the human disease are 
that in both there is an affection of the intestine (large intestine in 
man, cneca in turkeys) associated with liver disease due to aincebse. 

The intestinal wall in amoebic dysentery is greatly thickened, owing 
to an (edematous condition. It is also thickened in circumscribed 
areas and contains cavities filled with gelatinous-looking pus. The 
amoebae vary much in size and contain vacuoles. They are found in 
variable numbers in the bottom of the ulceus and in the discharges. 
The large numbers of amoeba* found in the intestinal contents led Coun- 
cilman and Lafleur to infer an active multiplication therein. The pres- 
ence of the parasites within the submucosa is described by these 
authors in one case 4 only. 

In the turkey we have seen that the parasites are always present in 
the connective tissue spaces of the mucous and submucous membrane. 
Their presence in the contents of the crccuin is highly probable from 
examinations made last summer but not definitely settled, as it is diffi- 
cult to recognize the parasites in the feces. 

The microparasite of the turkey disease differs from the Amoeba 
dysenteries in being quite uniform in its appearance, varying but 
slightly in size (from 6 to 10 // in diameter) and in being free from 
vacuoles. Movements characterized as amoeboid have not yet been 
demonstrated. 

The liver affection in man appears usually as an abscess. In turkeys 
it appears as a variable number of foci in which the microparasites may 
be present in great abundance. The difference in the nature of the 
lesions must be largely attributed to the different reaction of the tis- 
sues of birds toward injuries. This brief statement must suffice to 
point out the analogy between the human and the avian disease, and 
the tracing of any further relationships must be left to those specially 
interested in this subject. 

Before concluding the discussion of the microparasite of this disease 
I desire to refer briefly to peculiar organisms found in the lumen of the 
tubules of the creca. Fig. 5 of PI. V depicts these bodies very well. 
The figure represents a cross section of one of the tubules from the 
diseased csecuin of No. 26. It will be noticed that the tube is packed 
with minute organisms of a roundish or oval outline provided with a 
more deeply stained body, probably a nucleus. The organisms, after 

1 For a good resume", with citations of the literature, the interested reader is referred 
to Schuberg: Centralblatt fiir Bakteriologie, XIII (1893), Nos. 18 to 22 inclusive. 

2 W. T. Councilman and II. A. Lafleur. Amoebic Dysentery. The Johns Hopkins 
Hospital Reports, II (1890-91), pp. 395-548. 

3 W. Kruse u. A. Pasquale, Untersuchungen iiber Dysenterie und Leberabscess, 
Zeitschrift f. Hygiene, XVI (1894), pp. 1-149, 

•»Loc, cit., p. 490, 



RELATION OF BACTERIA TO THE DISEASE. 21 

being fixed in corrosive sublimate and hardened in alcohol, measure 
from 4 to 5 /.i in diameter. The nuclear body, though it appears round 
or oval in the figure, is actually more complex in form. Careful focus- 
ing with a high power (x 1,000) shows a spindle-shaped or oval body 
which may be bent like the arc of a circle. Its shortest diameter is 
about 1 //. At first I was inclined to look upon these bodies as blood 
corpuscles which had escaped into the tubules during the disease 
process from the cavity of the caecum. This view is made very improb- 
able by a number of facts. The red corpuscles in the capillaries of the 
same section are quite different from these bodies, both as regards the 
color of the hemoglobin, and the form, size, and structural appearance 
of the nucleus. These problematical objects assume a bluish-pink color 
when stained in hematoxylin, and the nucleus stains quite deeply and 
solidly. Again, it would be difficult to understand why all the tubules 
should become packed with these bodies if they were blood corpuscles. 
Another supposition, that they might be some stage of the microparasite 
of this disease does not harmonize with the fact that they are found 
within the tubules of the healthy c;ecum (No. 47). They may be 
absent in cases where the disease is most active (No. 3). On the other 
hand, they were very abundant in No. 20, and less so in No. 10. 

The most satisfactory assumption is that these organisms represent 
one of the unicellular animals, probably a flagellate. It is interesting 
to note that flagellates were found in large numbers in the fresh con- 
tents of the crecuin of No. 47, in which these bodies were found within 
the tubules in sections of hardened tissue. 

There is probably no genetic relation between this hypothetical 
organism and the true parasite of the disease under consideration. 
The latter is larger, its nucleus is smaller and simpler in form, and its 
behavior toward staining reagents is different both as regards the 
cell body and the nucleus. It would seem, on the whole, that we have 
here a microorganism which inhabits the caecum and by preference the 
depths of the tubules. Its effect upon the health of the turkey can, of 
course, be only conjectured at present. 

THE RELATION OF BACTERIA TO THE DISEASE. 

From what has been stated concerning the presence of the protozoan 
parasite in the diseased tissues, there can be little doubt that they 
must be regarded as the cause of the disease. In the course of the 
investigations the possible bearing of bacteria upon the disease was 
not entirely overlooked and cultures mainly upon agar were made from 
the blood and the liver of a considerable percentage of the infected 
turkeys. Usually, bits of liver tissue were transferred to the culture 
tubes. Of the heart's blood, one or two loops were inoculated. The 
results obtained varied from case to case. As a general rule, tubes 
inoculated from birds that had just been killed remained free from 
growth, whereas the cultures of those which had died during the night 



22 INFECTIOUS DISEASES AMONG POULTRY. 

and were examined next morning were quite regularly fertile. The 
bacteria isolated from these cultures were examined by Dr. C. F. Daw- 
son, assistant in the laboratory, and most of them found to be B. coli 
communis. Several of these were afterward reexamined by me and his 
results confirmed. 

The absence of any uniformity in the bacteriological results as well as 
the appearance of B. coli in the organs of dead turkeys indicates that 
pathogenic bacteria were not associated with the protozoa in the cases 
examined. It furthermore warns us to be careful not to attribute to 
such bacteria as may be found the power of producing disease, as has 
been lately done by Lignieres, * who found B. coli in the organs of a 
small number of dead fowls and claimed, without positive proof, that 
they were the cause of a septicaemia. 

THE RELATION OF THIS DISEASE TO CERTAIN OTHER DISEASES OF 

POULTRY. 

(1) To other diseases of the cceca in turJceys. — In the investigations 
made in Rhode Island three cases came under my observation which 
make it certain that not all diseases affecting the caeca of turkeys are 
due to the protozoa described. 

Of one case (No. 7) only the intestines were obtained. One of the 
attached caeca was greatly distended by an exudate, similar to that 
found in some cases of the protozoan disease. At about 1 inch from 
the blind end the caecum abruptly swelled out to a diameter of 1^ inch. 
The enlarged portion was about 2 inches long and very firm to the 
touch. The whole mass was placed unopened in alcohol. When it 
was subsequently opened the enlargement was found due to a firm 
exudate with a narrow canal passing through the center. The exudate 
readily peeled away from the wall, which was bat slightly thickened. 

The second case (No. 2.1) was similar to this. Only one of the caeca 
was affected. The notes on this case are as follows: 

One caecum slightly distended by a rather firm cylindrical mass of feces encased in 
a Avhitish leathery exudate made up of concentric layers. The whole is not adher- 
ent to the mucosa. This membrane is dull, slightly congested. The wall is very 
slightly thickened. The liver is free from disease. 

In the intestines are numerous tapeworms. Two cultures were made by placing 
bits of liver tissue in tubes of inclined agar. In both, colonies appeared. These 
were subsequently found to be closely related to B. coli communis. 

In the third case (No. 41) both creca were diseased, the liver normal. 

One caecum was very much distended over a distance 3 inches long, attaining a 
diameter of three-fourths of an inch. From the serous aspect the wall appeared very 
hyperaunic. When the tube was slit open the distension was found due to a cylin- 
drical mass of exudate, very firm, yellowish white. The exudate appears deposited 
in concentric layers. The lumen of the tube within this exudate was almost 
occluded. Odor strongly fecal. The exudate easily peeled away from the wall in a 
single mass. The wall was smooth and hyperaemic and but slightly thickened. 

1 Septicajmie a coli bacille chez la poule. Compt. rend. Soc. Biol. 1894, p. 135. 



RELATION TO OTHER POULTRY DISEASES. 23 

This exudate was hardened in alcohol aud transverse sections cut from it. These 
show that it is composed almost exclusively of a meslnvork of amorphous material, 
probably fibrin. Cell groups were found in but one locality of the exudate. 

The other crecum is only slightly distended. It contains a mass of exudate about 
1 inch long and one-third of an inch in diameter lying loose in the cavity. The 
mucosa is roughened and covered with a thin slough or exudate. 

Sections of the wall of this caecum show the mucous membrane replaced by a 
layer of young connective tissue cells in which tubules are absent excepting in cir- 
cumscribed regions in which the remnants of the tubules are still recognizable in the 
amorphous mass adhering to the submucosa. The muscular coats are not penetrated 
by cell masses, but the vessels of these and the subserous membrane are greatly 
distended with corpuscles. 

The small intestine of this turkey contained numerous small tapeworms. 

Two agar cultures were made from heart's blood and one with a particle of liver 
tissue. In one of the blood cultures a number of similar colonies developed. The 
bacilli composing one of them had all the cultural characters of B. coli communis. 

These three cases are of interest as indicating the existence of some 
other agency, probably bacterial in nature, which affects the cteca of 
turkeys. It differs from the protozoan disease in the entire absence of 
any liver affection and in the absence of any marked thickening- of the 
walls of the c<£ca. The exudate is much more abundant and obstruct- 
ive than in the protozoan disease. Further investigations are neces- 
sary to define more clearly the nature of this affection and its cause. 
A similar affection of the cwca was found in two turkeys by Von Eatz 
in Budapest. 1 

He found much thick mucus in the mouth and esophagus. The mucous membrane 
of the small intestine was studded with hemorrhages aud small, removable pseudo- 
membranes as large as lentils. Both ceca of one turkey contained a partly dried, 
cylindrical mass, and many minute worms 8 to 14 mm. long. In one caecum of the 
other turkey the same dry, cylindrical mass, easily removable. The mucous mem- 
brane itself was covered with layers of pseudomembrane. The other caecum was 
distended with gases and a grayish, semirluid mass. Both contained many round- 
worms. 

The author does not hesitate to attribute the crecal disease to the 
roundworms. This conclusion is, however, merely an inference based 
on the presence of worms aud exudate. It is more than probable that 
the disease is bacterial and secondary to the catarrhal affection of the 
mouth. 

(2) To disease of the ccvca in fowls. — This is by no means uncommon. 
Ziirn 2 considers it a form of diphtheria which may affect the various 
parts of the head, the digestive and respiratory organs. He states that 
the disease of the caecum may appear as an independent affection in 
water fowls and turkeys. The disease is accompanied with great 
depression aud weakness. The diarrhea which appears is at first semi- 
fluid and mucous, later it becomes fluid and is mixed with blood. The 
foul- smelling discharges may be followed by constipation, and then the 

1 Blinddarmentziindungen bei Truthiihnern (lurch Ascariden veruraacht. Deutsche 
Zeitschrift f. Thiermed., XX (1893), p. 74. 
2 Deutsche Zeitschrift f. Thiermed., X (1883), p. 189. 



24 INFECTIOUS DISEASES AMONG POULTRY. 

caeca and the rectum are found after death filled with yellow croupous 
masses in layers upon the frequently ulcerated mucous membrane- 
The disease lasts fourteen to twenty days or even two to three months. 
Often a relapse follows an apparent cure. He states that it frequently 
happens that the croupous or diphtheritic affection of the throat, nose? 
and eyes appears healed, when suddenly the intestinal disease breaks 
out and usually ends fatally. 

The writer has seen two instances of disease of the caecum in fowls. 
In one case one csecum had its walls very much thickened. The same 
was true of the second case. In this the thickening- was due to a 
reparative inflammation following" the loss of a greater part of the 
mucous membrane. In sections of hardened tissue protozoa were not 
recognized. It is probable that in this .fowl the disease was secondary 
to a dipththeritic affection of the head. 

Siedamgrotzki ' describes a disease of both creca in a hen. They 
were very much enlarged. In one caecum the wall was thickened by 
inflammation, but the mucous membrane was intact. In the other the 
wall was also thickened and adherent to neighboring organs. The 
mucosa was covered with a yellowish-brown, thin, pseudomembrane. 

Disease of the caeca in poultry seems to be a widely distributed 
affection, both primary and secondary to other diseases, and evidently 
due to more than one agency. It is to be hoped that more will be known 
concerning these affections in the near future, and that the demonstra- 
tion of one specific cause in the form of protozoa will pave the way for 
the determination of the others. 

GENERAL CONCLUSIONS. 

In the preceding pages we have shown that there prevails a disease 
of turkeys which attacks the young by preference, which runs no reg- 
ular course, but varies from bird to bird in severity, duration, and 
termination. It begins in the creca and thence invades the liver 
through the blood. Though restricted to these two organs, its action 
is severe enough to prove fatal to many affected turkeys. We have 
seen that the disease process is always associated with a protozoan 
parasite of very minute size, whose destructive action is due in the 
main to its powers of rapid multiplication within the tissues. It is 
probably discharged with the droppings of the diseased birds. These 
are the main facts learned by the brief investigations of last summer. 
While we may make certain conjectures as to the modes of transmis- 
sion of the infectious agent based on these investigations, we are at 
present unable to go further than this until experiments have been car- 
ried forward in other directions. 

From our present standpoint I think it safe to assume that the micro- 
parasite is transmitted from bird to bird without passing through 

'Bericht ii. d. Veteriuiirwesen im Kouigreich Sachsen, 1872, p. 84. 



CONCLUSIONS. 25 

any intermediate host. The microparasite, discharged perhaps in an 

encysted stage from the sick bird, is taken up with the food and water 
by others and sets up disease directly. 

If the parasites were taken up with insects, for example, we should 
expect to find the disease diffused through all Hocks. But even the lim- 
ited experience of last summer leads me to believe that certain flocks 
only are infected and that by uninterrupted transmission the disease 
becomes perpetuated and diffused among- neighboring flocks. The 
perpetuation of the parasites I am inclined to think is to be sought for 
in the older turkeys, which carry them in their body, most likely in 
the digestive tract during the winter. This view is supported by the 
fact that turkeys not infrequently recover from the disease. This re- 
covery does not mean, however, the destruction of the parasite within 
the body, for we have now information concerning the persistence of a 
variety of parasites — bacteria and protozoa — within the body long after 
recovery. 

The evidence which I have presented in this report seems to show 
that the turkey is iufected early in life and that infection does not take 
place later on. If this be so, the transmission from the old to the young- 
is easily understood. If the susceptibility to infection remained for any 
length of time we should expect to find the two caeca infected in every 
case. But in 7 out of 18 cases only one caecum was found diseased, 
the other normal. It is true that other explanations of this condition 
referable to acquired immunity, might be given, but the one cited seems 
to be the most acceptable. 

If the theory that the disease is transmitted more or less directly 
from old to young should prove to be true, the remedy for such a state 
of affairs would appear to lie in two directions: 

(1) The disease might be allowed to go on and some remedy found 
which will check it and lead to a cure; or 

(2) The diseased flocks might be entirely destroyed and new birds 
obtained elsewhere, after a thorough cleansing and disinfection of the 
territory formerly occupied by the flocks. 

The latter alternative, though very heroic and severe at first, seems 
to me the best in the end, especially as we might search in vain for a 
remedy which will check the disease in the young. Anticipating the 
investigations somewhat in this direction, I had hoped to determine 
the distribution of this disease in the country at large by an appeal for 
the shipment to this Department of diseased turkeys or organs there- 
from. Up to the present no material has been received, so that the 
study of distribution has made no progress. 1 It is evident that if the 
disease must be weeded out by a destruction of whole flocks it is highly 
important to find some locality free from such disease from whence new 
stock may be obtained. To obtain such information is by no means an 

ir rhe casca of about 30 turkeys from the Washington markets were examined 
during February of 1895, and found free from disease. 



26 INFECTIOUS DISEASES AMONG POULTRY. 

easy task, and may be made still more difficult by the infusion of a 
certain amount of local pride and self-interest. The disease is, how- 
ever, readily recognized in most cases, so that anyone who has examined 
the plates of this article and read certain portions of the text may be 
able to detect it. The peculiar circular spots on the liver, coupled in 
later stages of the disease with the presence of yellowish cheesy masses 
or whitish scars in this organ, are very characteristic and probably 
peculiar to this affection. Disease of the caeca, unless accompanied with 
the spots on the liver, should not for the present be regarded as belong- 
ing to this affection. 

When we come to the subject of treatment some difficulties arise. 
Though turkeys may appear drooping, unable to keep up with the move- 
ments of the flock, and even have diarrhea, the precise nature of the 
disease is not made clear by these symptoms. Among the 50 turkeys 
examined many were taken alive as suspicious cases. When killed the 
protozoan disease was not found. They were suffering from a variety 
of other affections, the causes of which, mentioned in the order of fre- 
quency, were lice, tapeworms, gapeworms, ticks, injury, and a diphthe- 
ritic disease of the caeca likely to be mistaken for the genuine protozoan 
disease. The same treatment applied to such a variety of disorders can 
hardly be looked upon very hopefully. Still, the subject merits attention. 
The success which quinine has had in combating malaria leads me to 
suggest its use to those who are in a position to experiment with this 
disease. Since the microparasites are embedded in the walls of the 
ca'ca and in the liver the remedy to be tried must do more than act 
locally in the intestines. It must act upon the parasites through the 
blood, and its effect on the diseased turkey should be carefully watched 
to note any poisonous action. 

The disinfection of the coops and other structures designed to give 
shelter to turkeys, and other poultry as well, should be carried on as for 
bacterial diseases until further investigations shall have been made. 
The following disinfectants are strong enough to kill spores of bacteria, 
and will probably destroy the various stages of the protozoa: 

(a) Corrosive sublimate (mercuric chloride), 1 ounce in about S gallons 
of water (one-tenth of 1 per cent). The water should be put into wooden 
tubs or barrels and the powdered sublimate added to it. The whole 
must be allowed to stand for twenty-four hours, so as to give the subli- 
mate an opportunity to become entirely dissolved. Since this solution 
is poisonous, it should be kept covered up and well guarded. It may be 
applied with a broom or mop, and used freely on all woodwork. Since 
it loses its virtue in proportion to the amount of dirt present, all manure 
and other dirt should be first removed before applying the disinfectant. 
The manure should be covered with lime. 

(b) Chloride of lime, 5 ounces to a gallon of water (I per cent). This 
should be applied in the same way. 



APPENDIX. 27 

(c) The following disinfectant is very serviceable. It is not poisonous, 
but quite corrosive, and care should be taken to protect the eyes and 
hands from accidental splashing: 

Gallon. 

Crude carbolic acid i 

Crude sulphuric acid ! 

These two substances should be mixed in tubs or glass vessels. The 
sulphuric acid is very slowly added to the carbolic acid. During the 
mixing a large amount of heat is developed. The disinfecting power 
of the mixture is heightened if the amount of heat is kept down by 
placing the tub or glass demijohn containing the carbolic acid in cold 
water wjhile the sulphuric acid is being added. The resulting mixture 
is added to water in the ratio of 1 to _!0. One gallon of mixed acids 
will thus furnish 20 gallons of a strong disinfecting solution, having a 
slightly milky appearance. 

(d) Ordinary slaked lime, though it does not possess the disinfecting 
power of the substances given above, is nevertheless very useful, and 
should be used more particularly on infected soil. 

APPENDIX. 

In the following pages is given the history of the turkeys which have 
been examined up to the time of the completion of this bulletin. It was 
thought best to include the brief notes of those turkeys affected with 
maladies other than those of the infectious disease under consideration, 
to illustrate the existence of such affections and the necessity for fur- 
ther investigations. 

Turkey No. 1. — Portions of the liver, caeca, and lungs received in weak alcohol 
about the middle of October, 1893, from Mr. Cushman. Age of fowl not known. 
Lungs dark, congested. The wall of the caecum is fully 5 mm. thick. In the liver 
are disseminated firm yellowish masses simulating the cheesy matter in tuberculosis. 
Tissues not in very good condition for microscopic examination. They were, how- 
ever, placed in absolute alcohol and subsequently cut in paraffin. Sections of lung 
tissue show all vessels densely packed with red corpuscles. No other changes. 

Sections of the thickened wall of caecum stained iu alum carmine, hematoxylin, 
and eosin, methyl violet, according to Cram, and in Weigert's fibrin stain. The 
hematoxylin proved to lie the best. 

The thickening of the wall is due in the main to cell infiltration of the submucous 
tissue. The entire mucous membrane is sloughed away, and the submucosa presents 
a ragged appearance along the exposed border. Throughout the section, and more 
particularly near the serous aspect, there are many distended capillaries filled with 
blood corpuscles. The nature of the cellular infiltration not recognizable, owing to 
imperfect hardening. In certain areas there may be seen, however, a peculiar col- 
lection of cells having several nuclei and inclosing large vacuole-like spaces. These 
spaces were subsequently recognized as having been occupied by protozoa. These 
phagocytes, with several nuclei shaded oft" into exceedingly large giant cells, over 
80 j.L in diameter, often forming large patches by collecting into groups. They are 
quite uniformly dotted with nuclei, and contain relatively very few parasites. 

Sections of liver tissue showed an extensive substitution of the parenchyma by 
numerous and greatly dilated blood vessels within newly formed connective tissue. 



28 INFECTIOUS DISEASES AMONG POULTRY. 

In such areas only a few islands of liver cells are recognizable. Parasites not seen. 
Giant cells rare. 

Turkey No, ;'.'. — Liver and a portion of the intestine, with cseca attached, sent by Mr. 
Cu8bman from Rhode Island on April 2, 1891, and received April 5. Turkey probably 
a large one. 

Post-mortem changes well under way when organs were received. It was, how- 
ever, not difficult to recognize the disease. Only one ca-uui affected. About one- 
half of the tube, beginning with the blind end, is almost completely occluded with a 
firm, pale-yellowish exudate having the appearance of concentric layers when -cut 
across, like the rings of a tree. The occlusion is complete at the blind end. The 
tube, usually only 0.5 to 1 cm. (two-fifths inch) across, is distended to 2 cm. 
(four-fifths inch). The exudate is firmly attached to the greatly thickened walls. 
Sections <>f hardened tissue show that the entire wall of the caecum, or what is 
left of it, is densely infiltrated with round cells. The lesions characteristic of the 
earlier stage of parasitic invasion no longer recognizable. 

The liver is beset with a considerable number of circular, slightly depressed areas, 
which have a pale, mottled appearance. They vary in diameter from 5 to 10 mm. 
(one-fifth to two-fifths inch). When incised the same appearance is presented within 
the liver tissue, showing that these circular spots simply represent the surface of 
roundish masses of tissue which have undergone the same change. 

In sections of hardened tissue each disease focus is shown to be the scene of a com- 
plex process of destruction. The periphery consists of normal liver tissue, the capil- 
laries of which are distended, and gorged with red corpuscles. Within the diseased 
focus there is disseminated a peculiar meshwork of amorphous, homogeneous matter 
which stains but feebly in hematoxylin. Its meshes are large enough to hold one 
or more tissue cells. In some places it resembles more closely mammalian fibrin in 
its appearance. Liver cells are either entirely absent or present in isolated numbers 
where this substance appears. Besides this there are areas of considerable cell infil- 
tration and, scattered about without regularity, giant cells. Parasites are present, 
but in small numbers. 

From the liver bits of tissue were placed in three agar and three gelatine tubes. 
At the same time bits were placed under the skin of a rabbit and a guinea pig. The 
cultures remained sterile and the animals well. 

Turkey Xo. 3. — Small specimen ; probably 3 or 4 weeks old. Died in the morning of 
June 6, 1894, on a farm in Berkshire County, Mass. Examined several hours after 
death. Weather quite cold. In this case both ca>ca and the liver were involved. 
In the former the walls were considerably thickened, but there was no exudate 
within the tube and the mucous membrane appeared intact. 

In sections of the caeca hardened in alcohol and in corrosive sublimate the wall 
was found of variable thickness. In some regions it was nearly normal on one side 
and considerably enlarged on the opposite side. In others the entire cross section 
was uniformly thickened. The mucosa is still in position and but slightly altered. 
The cells of the crypts show extensive mucous metamorphosis. The enlargement of 
the wall is due mainly to an extensive infiltration of the submucosa and of thecircular 
band of muscular fibers with the protozoa. The muscular fibers are pushed apart into 
strands, or else entirely obliterated. . These microparasites are found throughout the 
entrre section in uniform abundance. They are comparatively rare in the reticular 
tissue of the mucosa between the crypts. In the fresh contents of the ca>ca were 
found coccidia with distinctly double-contoured Avail. The long axis measured 15 
to 20 //, the short 10 to 13 /.i. 

The liver of this bird was dotted with about a dozen circular spots, A'arying in 
size, some 7 mm. in diameter. These spots consist in the main of minute yellowish 
lines embedded in the liver tissue and loosely interlacing to form a circular wheel- 
like area. They thus differ from some other cases to be recorded in less destruction 
of liver tissue within the circular area, for the yellowish lines represent necrosis of 
liver tissue. 



APPENDIX. 29 

In sections of liver hardened in corrosive sublimate and alcohol the foci of disease 
no longer contained any liver tissue. This is replaced by numerous microparasites 
surrounded and enveloped in a meshwork of reticulated tissue rich in nuclei. Giant 
cells are present in moderate numbers. 

At the time this young turkey died two others were found dead and were exam- 
ined. Neither was affected with this disease. 

Turkey Xo. 4. — Has beeu dead for two days. Decomposition well under way. 
Obtained from a dealer. Extensive spotted disease of the liver and thickening of 
walls of ca'ca with exudation into the tube. 

Turkey Xo. 5 (Farm A). — Probably 8 to 9 weeks old. Received alive August 3. 
Blood from vein of the skin examined. A few fusiform flagellates seen. Nothing 
abnormal with the corpuscles. Killed. On the neck a small tick. Mouth, trachea, 
and luugs normal. The digestive tract normal with exception of the duodenum and 
the caeca described below. The former shows marked pigmentation in points and 
strhe (villi 1 ). In the rectum and cloaca contents pale-yellow, liquid, containing urate 
spheres in abundance and numerous flagellates. 

Both c;eca are diseased. They are unusually short, only one-half the length as 
usually found in turkeys of the same age (PI. I, fig. 2). Both are distended from one- 
half to three-fourths of an inch in diameter, and very firm, as if filled up. Vessels 
on the serous surface injected. 

The condition of one of them is shown in PI. II, tig. 2. The caecum is slit open 
longitudinally, and the cut surface exposed to view. The lower two-thirds of the 
tube is completely occluded by a firm exudate. On the cut surface the wall of the 
CSBCum is shown as an irregular line, indicating marked thickening along the whole 
length of the tube. The exudate is pale yellowish- white in color, excepting below, 
where it is largely made up of a blood clot. The main mass contains centrally an 
irregular cavity. Above, the tube is filled with small round stones, probably dis- 
charged from the gizzard. The other caecum has its wall very much thickened, as 
shown in PI. II, fig. 3. The exudate is also present, but not attached to the walls in 
the alcoholic preparation. 

The liver, which is enlarged slightly, is spotted on all surfaces with isolated and 
continent areas of a circular outline and pale yellow in color. They rarely exceed 
4 mm. (one-sixth inch) in diameter. On closer scrutiny the yellowish color is seen 
to appear as a network. These disks correspond to masses of diseased tissue within 
the substance of the liver. 

In crushed, fresh tissue are found isolated and agglomerated bodies of a round 
form, with a homogeneous colorless disk and a single-contoured outline (PI. V, 
fig. 1). Near the center of these bodies is seen a small mass of very hue refrangeut 
granules. They are 8 to 10 fi in diameter. One per cent acetic acid will not affect 
their appearance. 

Three cultures on inclined agar were made with a large aud two small bits of liver 
tissue and a large bit of spleen tissue (about the size of a pea). Furthermore, tubes 
were inoculated with a loop of blood and with a loop driven into the liver tissue. 
The six tubes remained free from growth. 

Turkey Xo. 6 (Farm B). — Selected because of slightly reduced condition. Cooped 
for two days. Found dead August 5. 

In abdomen some blood-stained serum. Considerable kyperamia of serous cover- 
ing of gizzard and of mesenteries. The blind ends of caeca knotted inextricably 
together, enveloped in a mass of yellow exudate, and attached by means of it to 
neighboring coils of the intestine and to the abdominal wall. The latter is infil- 
trated and discolored at this point. After some dissection it was found that only 
one caecum was primarily diseased. This was filled with an exudate at the blind 
end for a distance of three-fourths of an inch. 

The liver is somewhat enlarged, and on its surface are a small number of pale 
yellowish areas fully one-half of an inch in diameter. They correspond to masses of 
similarly affected tissue in the liver. 



< 



30 INFECTIOUS DISEASES AMONG POULTRY. 



J 



Sections of liver tissue hardened in alcohol were made through these large pale 
spots. Iu these only small fragments of recognizable liver tissue were found inter- 
spersed in the diseased focus. Much of this was occupied by a meshwork represent- 
ing necrosed liver cells fused together. Small necrotic foci were also detected outside 
of the main focus, embedded iu still unchanged tissue. The necrotic meshwork is 
arranged in spots generally connected, the interspaces being filled up with groups 
of minute cells and occasional patches of microparasites. Giant cells are common, 
usually within or on the circumference of the necrotic areas. The microparasites 
are also inclosed in these cells. The scarcity of these bodies makes it probable that 
the disease is not longer progressing. 

Cultures were made by transferring a loop of heart's blood and a loop which had 
been forced into the liver through a scorched area to inclined agar. 

The blood culture remained sterile. The liver culture contains manifestly several 
species, only one of which was studied, and found to resemble B. coli. 

Turkey No. 7.— Received from a dealer the intestines of 16 turkeys for examination. 
In one of these there was disease limited to one ciecum. (See page 22.) 

Turkey No. S (Farm C).— Received about August 3 and cooped temporarily. 
Found dead August 6; alive the day before. 

The lesions in this animal are restricted almost entirely to the caeca. In one 
caecum the mucosa is beset with about eight peculiar elevations, which have a central 
yellowish slough and a surrounding infiltrated zone, making the whole crater-like 
body about three-eighths of an inch in diameter. On the serous surface some of 
these necroses show as whitish, discolored areas, with injected border. 

The other caecum contains but one ulcer. In the liver several small areas are 
found which appear necrotic, but whose nature is doubtful. 

Transverse sections of a portion of the wall of the ciecum hardened in alcohol 
jf were made through one of the ulcers. The mucous membrane had sloughed away 
over the center of the ulcer, and the submucous tissue and the muscular coat were 
extensively infiltrated Avith masses of cells. 

Two cultures were made on inclined agar, one with a loop of heart's blood, the 
other with a bit of liver tissue. The latter remained sterile. From the former two 
bacilli were isolated, one corresponding to B. lactis aerogenes, the other to B, coli. 

Turkey No. 9 (Farm D). — Brought to laboratory dead. Probably 3 months old. 
The disease is restricted to the ca»ca and the liver. 

In one caecum there are three, in the other four, thickenings of the wall, which 
appear as opaque yellowish spots under the serous covering. Two thickenings are 
situated near the blind end, the rest near the attached end. From the mucous sur- 
face they appear as yellowish spots from one-eighth to three-sixteenths of an inch 
thick in the center and thinning out from that point. 

The liver is beset with large, isolated and confluent roundish patches of a grayish 
color, mottled with yellowish specks. The same appearance is presented by the cut 
surface. 

In crushed preparations of the liver a few round, uniformly granular bodies, some 
within what appear to be the remnants of cells, detected. 

Sections of liver tissue hardened in alcohol present the usual appearances charac- 
teristic of the disease. Sections passing through the circular spots show that a 
considerable area of such spots consists of the homogeneous meshwork resulting 
from necrosis and fusion of the liver cells. In some of these, giant cells are situ- 
ated, singly or in groups, many of them inclosing vacuoles which represent the 
former seat of microparasites. The regions not occupied by necrotic tissue are 
largely made up of cells which have a small, round, densely-stained nucleus, envel- 
oped in considerable protoplasm. The nature of these cells is unknown, although 
it is probable that they correspond to the round cells in the inflammatory processes 
of mammalia. In the liver tissue beyond the diseased circle isolated foci are pres- 
ent, which are made up mainly of the cells described and gome interspersed giant 



APPENDIX. 31 

cells. Throughout the diseased area the various cell forms are undergoing degener- 
ation. This manifests itself hy a breaking up of the nuclear (substance into stained 
granules of limited number. This phenomenon is especially frequent in the epithe- 
lium of the bile ducts, and more rarely the giant cells themselves show this degener- 
ation. 

Sections were also made through one of the thickenings in the wall of the caeca. 
These showed that the thickening was due in the main to a very extensive cell 
infiltration of the submucosa and of the muscular portion of the wall. Under the 
serosa the blood vessels are much dilated, and gorged with red corpuscles. The 
mucosa is not thickened, but is more or less infiltrated at the base. Much of the 
epithelium is gone, both of the surface and of the tubules. 

The microparasites are poorly preserved, but a little scrutiny shows them to be 
present in certain regions of the mucosa, submucosa, and rarely in the cell masses 
between the displaced muscular bundles. In the mucosa and submucosa they have 
invaded large patches, and here they are ranged side by side and are inclosed in a 
reticular tissue, each parasite by itself. Giant cells are also present in groups, 
usually consisting of little else than a mass of parasites enveloped in a nucleated 
network of protoplasm. 

Turkey No. 10 (Farm E). — Probably 8 to 9 weeks old. Supposed to be infected 
because unthrifty. Cooped for a few days. When killed no lesions found. On the 
skin were some ticks and lice: in the intestines a few tapeworms. 

Turkey No. 11. — From the same flock and in the same condition as No. 10. No 
lesions found when animal was killed. A few ticks on border of meatus of ear. 
Lice abundant. 

Turkey No. 12 (Farm C). — Probably 3 weeks old. Cooped for a week before it was 
killed. A few flagellates in blood from veins of skin. 

Tapeworms iu upper small intestines. In soft contents of caecum immense num- 
bers of flagellates. No disease of caecum or liver. 

Two cultures made with bits of liver added to agar remained sterile. 

Turkey No. 13 (Farm F). — Brought alive, because suspected of being diseased. No 
lesions discovered on dissection. Many small tapeworms in duodenum. In ca-cal 
contents many flagellates. 

Turkey No. 14 (Farm G). — About 3 months old. Taken from a flock August 8 be- 
cause of lack of strength to keep up with the rest when driven. Indications of diar- 
rhea. Placed in a coop, where it died diiriug the night. Examined next morning. 

Slight odor of decomposition. A few small warts on skin of neck. The various 
organs were found normal, with the following exceptions: 

Mucosa of duodenum' almost blackish, from intense injection and pigmentation of 
villi. 

Both cjeca diseased. The left is slightly distended. On serous aspect two yellow- 
ish spots, with markedly injected binders, corresponding to thickenings of the walls 
near the blind end of tube. The mucous surface of one is smooth ; to the other an 
exudate is attached. Besides the thickening at these spots, the free half of this caecum 
is somewhat thickened uniformly. 

The right c;ecum is very much distended over two-thirds of its length. From the 
serous surface local thickenings are recognizable, which have a yellowish, mottled 
appearance. The small intestine is firmly attached to one of these. The disease has, 
however, not invaded the wall of the latter. The border of these spots is intensely 
hyperaemic. When the ca;cum is slit open its width is three to four times that of the 
undistended tube, and the thickness of the wall varies from one-eighth to one-half 
of an inch, being not less than one-eighth of an inch over three-fourths of the entire 
length. When the brownish feces were washed away the increased local thicken- 
ings were found covered with firm exudates, usually attached in but one spot. 

Sections were examined of that portion of the csecal wall which was very much 
thickened, and to which the contiguous small intestine was inseparably attached by 
the new growth, 



^ 



32 INFECTIOUS DISEASES AMONG POULTRY. 

The mucosa of the caecal portion had sloughed away, while that of the emhedded 
small intestine was intact. The neoplastic tissue between caecum and intestine 
was fully 1 cm. (two-hfths inch) thick. Inasmuch as the infiltration probably fol- 
lowed the narrow mesentery between caecum and intestine the original boundary 
lines of the caecal wall are no longer recognizable. The muscular coat of the caecum- 
may be traced for only a short distance into the neoplasm, when it disappears. Micro 
parasites were not seen distinctly in the diseased tissue. 

The liver is very much enlarged, and dotted everywhere with roundish spots of 
varying appearance. The majority are from 5 to 12 mm. in diameter, round or slightly 
oval. The center of each is usually occupied by a group of yellowish dots and the 
circle is bounded by a narrow yellowish ring. The space of the circle is mottled 
brownish. Among these spots there are also circles of a completely yellowish color 
On the convex surface of the left lobe there is a very firm, ring-like, yellowish mass, 
cutting like firm cheese. 

In crushed preparations of fresh liver tissue from within the brownish circles many 
giant cells are seen. They consist of a meshwork of protoplasm of a rather coarsely 
granular character inclosing spheres which appear homogeneous. The giant cells 
are up to 30 // in diameter. 

Sections of liver tissue hardened in alcohol and in Foa's solution were also exam- 
ined. The foci of disease contain necrotic areas in which are numerous giant cells 
each inclosing a number of microparasites. In some portions there is much cell 
infiltration in the interlobular tissue around the portal vessels. Among the cells the 
protozoa are recognizable. 

Turkey No. 15 (Farm H). — Obtained alive and killed. About 3 months old. No 
caecal or liver disease detected. In duodenum numerous tapeworms. This turkey 
had probably been injured, for blood extravasation was found under skin of skull. 

Turkey No. 16. — About 3 months old. Obtained with No. 14 from the same Hock 
(Farm G). Suffering with diarrhea. After being cooped for two days it was killed 
August 10. The blood taken from a cutaneous vein of the breast under the wing 
showed extensive leucocytosis. 

The digestive tract is normal, with following exceptions : The mucosa of duodenum 
is hypera-mic. Tapeworms absent. The rectum, i. e., the bowel from the cseca to 
cloaca, is also hypersemic. It contains yellowish masses made up of microscopic 
spherical crystals (urates). 

Both caeca are affected. Contents of a pasty, brownish (nearly normal) character, 
containing a considerable number of microparasites. Flagellates not seen. 

The disease is manifested in both c;eca symmetrically by a thickening of the walls 
of the distal half of each tube. There are a few yellowish Spots noticed under the 
serous covering of the thickened region. These correspond to spots of maximum 
thickness. The mucous membrane appears intact. The slight pigmentation noticed 
on the mucous folds is frequently present in caeca otherwise normal. 

In tangential sections of the thickened wall in the fresh condition considerable 
numbers of round microparasites, of a homogeneous-appearance, and about 8 to 10 n 
in diameter are seen. They are not bound to cells, but appear to be displaceable 
under the cover glass independently. 

In transverse sections of one caecum hardened in corrosive sublimate and alcohol 
the increase in thickness of the wall was found to be due to hyperplasia of the sub- 
mucous tissue and cellular infiltration of the muscular coat. The mucosa itself was 
intact, the epithelium in place. Interspersed in the hyperplastic suDinucosa are 
small nests of giant cells, some containing well-defined micioparasites, others only 
vacuoles, somewhat larger than the parasites. The latter are not diffusely scattered 
through the tissue, but restricted to these and a few other foci in which they exist 
free in the meshes of the tissue. The masses of cells between the bundles of muscular 
fibers resemble those of the submucosa and are free from parasites. 

The liver is considerably enlarged. The surface is not .smooth but slightly rough- 
ened. Scattered over the various surfaces there are in all six or seven yellowish-white 



APPENDIX. • 33 

homogeneous sclerotic areas which correspond to masses in the liver tissue. In cut- 
ting into the liver these foci are found to sheath the hepatic veins. Outside of these 
sclerotic foci the liver tissue is mottled with gray. In general, the entire liver 
appears to have passed through a process of sclerosis. 

In sections hardened in Foa's solution and in corrosive sublimate the pathological 
change going on is shown to he essentially a sclerosis following the protozoan infec- 
tion. Within the disease focus the liver tissue, recognizable as such, is present only 
in irregular patches of variable extent. The remainder has been replaced by an 
actively developing connective tissue, still rich in nuclei. Within these areas there 
is an extensive formation of bile ducts. Parasites were seen in but one spot, where 
a number of multinucleated cells had ranged themselves around what appeared to be 
an old thrombus. Here, beyond the encircling giant cells, a group of similar con- 
tiguous cells contained a small number of protozoa. The encircling cells themselves 
also contained a few, and one parasite was recognizable within the thrombus itself. 
Outside of these spots undergoing repair, the blood vessels are everywhere inclosed 
in sheaths of new connective tissue very rich in nuclei, encroaching slightly upon 
the liver tissue itself. 

Turkey No. 17 (Farm I). — About 3 months old. Found August 11 in a dying condi- 
tion in a tlock in which a considerable number had died during the past month. The 
only lesions found were a rather pale condition of the organs. In the small intestine 
numerous tapeworms. No liver or ciecal disease. In the caeca feces arc rather dry, 
and contain a considerable number of coccidia, varying slightly in size, the largest 
32 n long and 18 fi broad. 

Turkey No. IS. — From the same flock as No. 17, and quite sick when found. Killed 
and placed on ice over night. 

In this bird no marked lesions of any kind were noted. The duodenum was 
hypenemic and contained more or less mucus. The contents of caeca are fluid and 
contain numerous flagellates. Cultures on agar from blood and liver remain sterile. 

Turkey No. 19 (Farm J). — About3 to 4 months old. Taken August 11 from a large 
flock, because suspected of being diseased. Died shortly after being caught. Placed 
in refrigerator over night. In the pleuroperitoneal cavity a dark clot and much 
blood-stained fluid ; ecchymosis of the left abdominal wall. .Source of hemorrhage 
not detected; probably brought on while being caught. 

Organs very pale but not diseased, with exception of liver and the right caecum. 
In the latter there are two diseased areas. Near the blind end there is a ring-like 
thickening of the wall, which has a yellowish color from the serous aspect. The 
other area is covered with a small mass of exudate, and the thickening of the wall 
beneath it covers an area about one-half of an inch square. The remainder of the 
caecuni pigmented in spots and lines. 

The liver is very much larger than in the normal condition and covered every- 
where with circular spots of varying appearance. There arc : 

(1) Two completely necrotic, yellow masses of cheesy character, one in the base 
of each lobe. 

(2) Circles of a grayish-yellowish color throughout. 

(3) Spots of a mottled brownish appearance. The mottling represents distended 
vessels. 

(4) Spots like the preceding with a necrotic mass in the center. These spots vary 
in size up to a diameter of three-fourths of an inch. 

In crushed preparations of the fresh liver the microparasites are distinctly rec- 
ognizable. Some appear as free granular bodies, others are inclosed, either singly 
in a cell, or in groups in large cells. These inclosed bodies are usually free from 
granules and may show a minute nucleus. They measure from 10 to 13 // in diameter, 

In sections of liver tissue from this case hardened in alcohol the lesions were found 
to correspond to those in other cases. Sections through a brownish spot showed 
everywhere marked distension of the vascular channels. These were tilled with 

17897— No. 8 3 



34 INFECTIOUS DISEASES AMONG POULTRY. 

corpuscles. The parenchyma has largely disappeared and small cells have taken 
its place. In a few places of the section microparasites are found collected together 
in large patches. In these, giant cells are occasionally seen. 

Turkey Xo. 20 (Farm I. see Nos. 17 and 18).— Found in field resting on keel and 
moving along ground with aid of wings. Obtained August 11. Killed and exam- 
ined August 12. 

In trachea six pairs of gapeworras attached. In caecum and rectum a yellowish 
fluid (urates) containing many flagellates. No disease of liver or caeca. 

Turkey No. 21 | Farm K).— Picked out of a large flock August 11, 1891, because it 
was much weaker than the rest. No distinct appearances of disease. When killed the 
organs were found normal, with the exception of the intestines. A mass of exudate 
lying adjacent to rectum in abdominal cavity binds together rectum, tueca, and 
neighboring coils. Tim mass has a cylindrical shape and is about 2 inches long and 
three-fourths of an inch at greatest diameter. It consists of spongy yellowish 
exudate, incased in a smooth, leathery capsule. There is no disease of the mucous 
or submucous tissue in any part of the intestines. The exudate is evidently the 
result of a tear in the rectum which permitted the escape of feces into the abdo- 
men. These became subsequently permeated with and encased in fibrin while the 
tear healed up. Odor of this mass strongly fecal. A bit of liver tissue is placed on 
inclined agar. The latter remains sterile. 

Turkey No. :2. — Large female, over 1 year old. Died on Block Island during the 
night of August 12. Examined on the farm next day. No evidence of liver or 
caecal disease. In abdomen a partially smashed eggshell attached lightly to mes- 
enteries. 

Turkey Xo. 23 (Farm L). — About 3 months old. Received, dead, by express August 
14. Probably died two days ago. Slight odor of decomposition. 

Duodenum very much discolored by pigmentation. Both caeca considerably dis- 
tended. The left is normal, the right diseased. Fully one-half to two-thirds of its 
entire length beginuiug with the blind end is thickened. There are a number of 
centers where the thickness is increased. At one of these there has been an out- 
pouring of exudate on the serous membrane. The mucous surface of these local 
thickenings is covered with firm masses of exudate. 

The liver contains one sclerotic focus which has a whitish mottled appearance. 
It is otherwise normal. Three adult pairs of syngames in the trachea. 

In sections of the wall of the greatly enlarged caecum hardened in alcohol the 
lesions were of an advanced character. The mucosa was almost entirely sloughed 
away. Only a few remnants of the slough remained, containing some tubules recog- 
nizable as such. The submucous tissue was greatly thickened by cell infiltration, 
and the muscular coat was divided into sections by cell masses which exteuded to 
the serous membrane. Under the latter the blood vessels appeared greatly dilated 
and filled with corpuscles. The microparasites are still present, but in small num- 
bers. They appear in the neoplastic tissue in small patches inclosed by a fringe of 
round cells. Giant cells are numerous and arranged in groups. Only in one group 
were microparasites inclosed. 

Turkey Xo. 24. — Taken August 13 from a flock ou Block Island, because it was sus- 
pected of being diseased. Killed August 14. No lesions were discovered in the 
organs. One gapeworm found in the trachea and several minute tapeworms in the 
intestine. 

Turkey Xo. 25. — Taken from the same flock. When killed disease was found in 
one of the caeca. (See page 22. ) 

Turkey Xo. 20. — About 3 months old. Brought August 15 from a large herd 
(Farm G), and reported as having been feverish for a few days past. The bird is 
killed and found in well-nourished condition. 

Disease limited to one cwcuni and to the liver. Fully one-third of the caecum has 
its wall thickened. The thickening is most pronounced in spots, to some of which a 



APPENDIX. 35 

firm, pale-yellowish exudate is attached. A portion of the diseased tube is placed 
unopened in hardening fluids for farther study. 

The liver is enlarged t<> two or three times its normal size, and uniformly per- 
meated with closely set. but usually discrete, spots, varying in si/e. a few having a 
diameter of one-fourth of an inch. They are of a yellowish - g due to a 

fine yellowish network, of which the spot is in fact mad.' up. The details are well 
shown in the photographic reproduction and in the colored draw g III. 

figs. 1. 20 

In teased and crushed preparations ot' the fresh liver a large number o{ mi 
parasites are detected. They appear as round, pale, horn g - :h a 

sharp line as a border. They are less refrangent than fat globules, and su„_ it 
somewhat the color and refrangibility of myelin or Bui V$ - - they are found 

in the alveolar epithelium of the lungs of cattle. Their diameter ranges from 12 to 
14 a. Some are surrounded by a narrow rim of protoplasm, containing one or more 
nuclei, evidently the remains o{ a cell. 

Transverse sections of the diseased ca-eum show a mass of exudate occupying a 
portion of the lumen. In the exudate are embedded strips of perfectly preserved 
epithelium. Tin' exudate appears amorphous and contains small foci and even large 
patches oi cell masses, probably originating from the inttammatory processes going on. 

The thickening of the wall is due in this case chiefly To infiltration of the sub- 
mucous tissue. In one portion of the sections the muscular portion of the wall is 
infiltrated to the serons covering. Parasites are. however, not detected in the sub- 
mucous or muscular cell masses, but are situated exclusively and in very large iuim- 
bera in the reticular tissue of the mucosa, between the crypts. In this tissue, as 
well as in the epithelium of the crypts, numerous mitotic figures au kble. 

Giant cells are also present, but m small numbers. The micro:' 
generally singly, in cavities surrounded by one or more nuclei. In some places tew 
or many may be detected, packed away in a space of the reticular tissue. 

The parasites are well brought out m the tissue hardened in corrosive sublimate 
and alcohol, and stained in hematoxylin and eosin. They a] - round or 

slightly oval bodies, with a faint reddish tinge of the body and a'lninute blue, ring- 
like, central or eccentric body, probably the nucleus wry from t ; 
diameter. 

The lumen ol' the mucous gland is densely packed with bodies roundish in outline 
and about 4 u in diameter. The cell body is stained a homogeneous red with eosin. 
the nucleus bluish with hematoxylin. v S(,t ' P»g« 200 

Sections of the lt\ er w ere made front material hardened in alcohol and in cor: • 
sublimate and alcohol. They were stained in various w ays, the most satisfactory 
stain being hematoxylin and eosin. by which the nucroparasite was most clearly 
brought out. Methylene blue was also satisfactory in bringing the mioroparas 
into relief. 

The sections show within sonic of the areas indicated by the yellowish spots 
extensive disappearance o( the liver cells proper and the presence ot a meshwork or 
network of a homogeneous subs:. nice, which suggests a fibrinous exudate, although 
it has not the librillated structure o( mammalian fibrin. This meshwork is not uni- 
formly distributed over the affected area, but appears ua foci which are connected 

with one another. The space left is occupied h\ numerous parasites ami giant cells 
and an occasional group o( liver cells. In other foci the liver cells are replaced by 

a reticulum containing numerous parasites. Usually but one parasite is contained 

in a mesh and is elosoh surrounded b\ one or more nuclei. 

Turkey So. 37. — Taken from another Block [slant! Book as a auspioious 

About 3 months old. 

No lesions found in tins bird. In the trachea three gapew onus ; in the intestine 
main large tapeworms. 

Turkeys Aw, 98 and 9, Brought from Fishers Island, N<» JTork No lesions m 

these oaseQ Manx large tapeworms n>. the intestine, 



36 INFECTIOUS DISEASES AMONG POULTRY. 

Turkeys Nos. 30 and 31 (Farm J). — About 3 to 4 weeks old. Brought because 
they were not doing well. Killed. Intestine found nearly occluded with small 
and large lapeworras. 

Turkey No. 32 (Farm C). — About 3 months old. Killed August 17. No lesions 
found. In duodenum several tapeworms. In caecum flagellates. 

Turkey No. 33 (Farm B). — About 3 months old. In the blood from a subcutaneous 
vein some flagellates. No lesions in the internal organs. In duodenum some tape- 
worms. 

Turkey No. 34. — Obtained from Farm K August 18. Died on the way to laboratory. 

Bird about 10 weeks old. In body cavity blood-stained fluid. One-half of the 
left caecum, beginning at the blind end, has its wall thickened. The serous covering 
js reddened and shows a few yellow patches which correspond to certain specially 
thickened regions of the wall whose mucous covering is necrosed. 

The liver is large and covered everywhere with rather large, round, dark-brownish 
patches having a narrow, yellowish boundary line. These correspond to diseased 
foci within the liver. 

In fresh liver tissue, crushed or cut in sections, oval bodies 12 to 15 /< in diame- 
ter are present inconsiderable numbers. They appear homogeneous; contents not 
differentiated. Similar bodies, inclosed in groups of two or three in large cells, are 
also present. They are homogeneous, round in outline, from 8 to 12 u in diameter. 

In sections of liver tissue hardened in alcohol, when examined with a low power, 
an immense number of microparasites appear embedded in the tissue. These vary 
but slightly in size (8 to 9 fi). Throughout the invaded spot the blood vessels, large 
and small, are irregularly dilated and filled with red corpuscles, among which the 
parasites are not seen. The tissue between the blood vessels is no longer recogniza- 
ble as hepatic tissue. In some parts of the section it consists in the main of the 
round parasites, single or in small groups, each individual or group inclosed in a rim 
of protoplasm provided with one or more nuclei. There is thus inclosing the para- 
sites an imperfect meshwork present whose origin and nature is not evident. In 
some places it would appear that the parasites are embedded in the liver cell. The 
nuclei of such cells have undergone proliferation and some of these proliferated cells 
have degenerated into groups of minute, deeply-stained granules. The impression 
conveyed by such cells is that they are giant cells. They differ, however, from 
those giant cells which appear in a later stage of the disease. The meshwork of 
tissue which has undergone necrosis is present in but a few small areas. 

Turkey No. 35. — From the same flock as No. 34 (and No. 21). Obtained August 18. 
Died on the way. 

This case closely resembles the preceding. One-half the length of both cieca 
involved. The walls are thickened uniformly and in this portion are some small 
excrescences easily removed in tolo, leaving only a slight depression. 

Liver spotted on all surfaces as iu preceding case. Duodenum blackish from 
injection and pigmentation. Muscular tissue has a yellowish tinge. 

In the trachea one gapeworm, and some roundworms in the duodenum. 

Turkey No. 36 (Farm N). — About 3 months old. Obtained, just dead, on August 18. 

In tli is case the liver and ca-ca are diseased. The liver is spotted on all surfaces. 
The spots vary in appearance. A few have a mottled, pale-yellowish aspect and 
are fully 1.5 cm. (three-fifths inch) in diameter. The remainder are round blotches 
of a mottled, dark-brownish appearance. Many of these have coalesced into small 
groups. 

The wall of the left caecum is very slightly thickened and still smooth. The right 
is in the same condition. At the middle it has a circular ring-like thickening, about 
2 cm. (four-fifths inch) wide, of a yellowish appearance on section. Sections were 
prepared of this region after hardening the entire caecum iu alcohol. 

The thickened wall, about 8 mm. in diameter at the thickest portion, consists 
entirely of neoplastic tissue. The mucous layer is gone and the muscular layer is 



APPENDIX. 37 

no longer recognizable. The bulk of the enlarged wall is composed of small cells, in 
which are interspersed in round and elongated patches large numbers of multinu- 
cleated cells, much smaller in size than the giant cells usually encountered. The 
cells do not distinctly show the microparasites within their suhstauce except in a 
few cases, probably owing to the time and manner of hardening. 

Turkey No. 37. — Obtained August 18 from Farm O. About 4 weeks old. Died the 
following night. No lesions found, although intestine contained many tapeworms. 

Turkey No. 38. — From the same Hock as preceding. About 3 months old. Died 
during the following night. No lesions. One gapeworni in trachea, and very many 
small tapeworms in intestine. 

Turkey No. 39. — From the same flock. About 9 weeks old. Died the following 
night. Numerous tapeworms in intestine. 

Turkey No. 40. — From the same flock August 18. Cooped until August 20. On 
that day the bird was resting on its breast with eyes closed. Killed. Many small 
tapeworms in intestine. 

Turkey No. 41. — Probably 8 weeks old. Brought to laboratory August 18, 1894. 
Cooped temporarily and found dead August 20. Disease in this case limited to both 
ca3ca. ( See page 22. ) 

Turkey No. 42. — Obtained August 18 from Farm I. About 3 mouths old. Sus- 
pected of being diseased. When killed no lesions were detected. 

Turkey No. 43. — Obtained August 18 from Farm P. Cooped. Found dead August 
20. The only discoverable lesions were a puffing out of the tissue below one eye, 
due to accumulation of a glairy secretion (roup). The same exudate found in the 
trachea. Agar tubes inoculated with tracheal exudate remained sterile. Numerous 
tapeworms in intestine. 

Turkey No. 44. — Obtained from Farm Q August 18. Many turkeys are reported to 
have died on this place. Bird about 3 mouths old. No lesions found when it was 
killed. Many tapeworms in intestine. 

Turkeys Nos. 45, 46, and 47. — Obtained from Farm R August 18 and cooped for 
several days. When killed nothing abnormal detected. A few tapeworms in the 
small intestine of No. 45 and No. 47, and many in No. 46. In the semiliquid eon- 
tents of the c;eca of No. 47 very many flagellates. 

Turkey No. 48 (Farm S). — Obtained August 18. Cooped until August 21. Bird 
appears well. When killed a few tapeworms were found in the intestine. 

Turkey No. 49. — Received August 18, from a dealer, the intestines of nine turkeys, 
In only one of these slight traces of csecal disease. This is manifested by a nodu- 
lar, roughened condition of the mucosa of one caecum near the attached end. In 
all intestines tapeworms present. 

Turkey No. 50. — Obtained September 26 from a farm in the District of Columbia. 
Slight odor of decomposition. The internal organs are free from disease. In the 
trachea one pair of gapeworms. The head is badly diseased. On the root of the 
bill a projecting tumor overlapping the nares, which is about two-thirds of an inch 
in diameter. It is of a soft, medullary character and has a wart-like structure. 
Besides this large tumor there is a small nodule on the lid of left eye. Right eye 
completely closed by excrescences on the lid and cheesy masses in conjunctival sac. 
Cornea opaque. In one nasal passage a large cheesy mass. No liver or csecal disease. 

Turkey No. 51 (Farm B). — Received from Mr. Cushman, Kingston, R. I., Octobers, 
1894. Died on the way. Turkey quite large; probably 5 months old. Decompo- 
sition well advanced. The disease in this case was limited to the cieca, the liver, and 
the peritoneum. The intestine was covered in places by a firm, yellow pseudomem- 
brane fully 1 mm. thick, and the coils were glued to each other so that they could 
be separated only after much dissection. The caeca appeared as an irregular mass 
partly covered with the pseudomembrane. Attempts to dissect out both ca-ca were 
fruitless, as they were firmly attached to each other. Only one was diseased, how- 
ever. This was much enlarged, its walls thickened, and the mucous membrane 



38 INFECTIOUS DISEASES AMONG POULTRY. 

beset with large, firm masses of exudate. In the liver were two foci of disease, 
each about 1 cm. in diameter. One is made up of firm, pale-grayish tissue, probably 
largely cicatricial; the other is similar in appearance, but has small, yellow, cheesy 
masses disseminated through it. 

Owing to the very advanced stage of decomposition, cultures were not made. It 
was evident, however, that the cause of death was the septic peritonitis, which was 
secondary to the ctecal disease. 

Turkey No. 52.— Received, dead, with No. 51. Large male bird; probably 5 months 
old. Very little decomposition. 

Head free from disease. Heart and lungs normal. The pleuroperitoneal cavity 
contains a large amount of blood-stained serum. Serous coat of gizzard very much 
injected. 

Serous coat of proventrieulus dotted with elevated yellowish points and lines 
where the diseased liver lay in contact with it. Spleen small, contains a minute 
yellow focus; probably also the result of neighboring disease of the liver. 

Duodenum, and a portion of the intestine below it, intensely hyperaemic and pig- 
mented. A few small tapeworms present. Pigmentation and hyperemia gradually 
become less and disappear near openings of caeca: Below these the intestine is 
coated witli a yellowish liquid, largely composed of urates. 

Both caeca contain pigment spots, ami the longitudinal folds are pigmented. In 
one caecum, near the blind end, there is a thickening of the wall about half an 
inch across, covered with a brownish-yellow slough on the mucous side. The serous 
aspect is discolored, in part yellowish. This is the only lesion found in the caeca. 

The liver is very large, weighing 304 grams (10.7 ounces). It is extensively dis- 
eased. The lesions are best described by grouping them under several heads: 

(1) Necrosis of the liver tissue is present in both lobes in the form of large and 
small masses of yellow, firm, cheesy masses (PI. Ill, fig. 2). In the left lobe fully 
one-third of the lobe is converted into a single, yellowish, homogeneous mass, situated 
at the base or attached portion. The necrosed tissue is sharply defined from the 
adjoining living tissue by an irregular line. The main branch of the hepatic vein 
is bounded by the necrosed tissue, and the branches from the dead mass are occluded 
with pale, friable thrombi. In the right lobe, at the base or attached portion, there 
are several quite large cheesy masses of very irregular outline embedded in the living 
tissue and in part visible on the surface. Besides these large masses there are dis- 
seminated through the liver numerous smaller masses of cheesy tissue, either singly 
or in groups. These small foci arc usually associated with reparative processes. 

(2) Foci which have healed and cicatriced wholly or in part are represented by 
isolated regions, varying in size and attaining a diameter in one case of three-fourths 
of an inch. The appearance of these foci varies considerably. They may show as 
pale pinkish-gray spots penetrated by a network of vessels corresponding to the 
interlobular markings. Others may be the seat of scars and slight depressions char- 
acterized by increased vascularity and a pale pinkish-gray appearance on the liver 
tissue. Finally, they may be intermingled with small cheesy foci, which are located 
either centrally in the healed region or in numerous foci around it. 

Over the entire surface of the liver patches containing networks of enlarged ves- 
sels having a blackish color give the liver an injected appearance. There is nowhere 
an indication that the disease as such is still going on. The extensive destruction 
of liver tissue, as well as the repair, appear to be the result of an invasion of proto- 
zoa now completely checked. 

The false membranes which cover some of the healing spots on the liver and the 
abundant fluid in the abdominal cavity indicate a secondary infection with bacteria 
through the necrosed tissue. 



A PRELIMINARY INVESTIGATION OF DIPHTHERIA IN FOWLS. 
By Veranus a. Moore. 

[With I*]. VI.] 

It is well known that a disease which is characterized by tin- forma- 
tion of mi exudate on one or more of tin- mucous membranes of the 
head is widely distributed among the fowls of this country. Although 

its existence is of long duration its cause and the character of the 
exudate have not been satisfactorily determined. In Europe outbreaks 

of a malady comparable to this in their manifestations have been 
described as epizootics of fowl diphtheria. There sue in this country 
a few popular articles on diphtheria in fowls, but. generally speaking, 
the term most frequently employed to designate a disease on the heads 

of poultry is ''roup.'" 1 The range of morbid anatomy which this term 
originally indicated is not known, but its present conception is exceed- 
ingly broad, including, as shown by the American literature.- nearly, 
if not all, the noticeable disorders of the heads of poultry. 

Writers differ in reference to the nature of this d; Bfany 

poultry raisers consider it a local affection, having its origin in the 
improper care of the fowls, while others insist that it is a highly con- 
tagious disease. The latter class strengthen their position by clinical 
history, in which they show that fowls which had previously been free 
from this disease soon became infected after the introduction of one or 
more "roupy" fowls into their midst. Reports show that it is the 
usual experience that when the di introduced it almost invari- 

ably remains in a more or less chronic form for an indefinite period. 
notwithstanding the adoption of the best known methods of caring 
for the fowls. It is stated by Bennett that --it is undoubtedly ti 

1 The origin of this term is somewhat obscure, but it iss I to be a corruption 

of croup, and its application explained on account of a peculiar ho .: om- 

pauying the respiration of the affected birds. 

-This literature is confined for the greater part to articles in poultry an<l 
cultural papers and journals. They are written by poultry fanciers or farmers, who 
record their experience with the various diseases of fowls, and, as would be 
they deal more with the treatment than etiology, and while _ _ tire are of little 
value in the study of the cause and nature of the maladies of -which they tr 



40 INFECTIOUS DISEASES AMONG POULTRY. 

mitted from the sick to the well fowls by their drinking out of the same 
vessel, as the discharges from the nostrils of the sick birds contami- 
nate the water as they drink." 

The lesions and symptoms attributed to this disease are exceedingly 
variable. Among the more careful writers we find "roup" defined as 
"a purulent catarrhal affection of the air passages." The localization 
of the lesions, however, in the air passages is not universally sup- 
ported. It is usually stated to affect, to a greater or less extent, the 
conjunctiva and the mucosa of the mouth, pharynx, and larynx, as 
well as that of the nares. The first symptoms are said to be "dullness 
and loss of appetite, discharge from the nostrils, loud breathing, and a 
dry cough." This is followed by the appearance of an exudate on the 
mucosa of the nares, which extends in all directions, often covering 
the eyes with a cheesy substance. The secretions are said to occasion- 
ally accumulate within the sides of the face, causing them to swell to 
an extensive degree. The appetite is either very poor, or ravenous, in 
Avhich case the food is not digested. Emaciation follows and death 
may occur in from three to eight days, or, as is usually the case, the 
disease becomes chronic and the fowls eventually recover. 

The economic importance of fowl diphtheria appears to be greater 
than that of any of the other poultry diseases. There are no statistics, 
however, by which the total amount of loss from this cause can be even 
approximately obtained, but the numerous reports of its occurrence 
are sufficient to show that it is very large. Unlike a rapidly fatal 
disease such as cholera, the loss is not confined to the fowls which die, 
but in addition it includes a heavy shrinkage in the poultry products? 
due to the chronic course of the disease in large numbers of fowls 
which eventually recover. The small value of the individual and the 
fact that only a small percentage of those affected die has evidently 
caused the importance of the disease to be underestimated. It is evi- 
dent, however, that the frequency of its occurrence and its wide 
geographical distribution render this affection a serious obstacle to 
the poultry industry 1 of this country. In addition to the usual chronic 
form, there are, if reports are true, frequent epizootics in which thou- 
sands of dollars' worth of poultry are destroyed. 

In addition to the theory of contagion, there are many conditions 
mentioned in poultry literature under which this disease may be 
expected to occur. Thus, it is affirmed that fowls exposed to a draft 
at night will ordinarily become affected. The nature of the food, venti- 
lation, and cleanliness are also considered important factors in pro- 
ducing or preventing this malady. The exudates are described as 
both catarrhal and diphtheritic, but the description of the lesions is 
exceedingly indefinite. 

; The economic importance of this industry is little understood. The Eleventh 
Census shows that in 1890 there were in the United States 258,472,15") barnyard 
fowls (exclusive of dncl<s, turkeys, and geese), aud that the egg product for 1889 
was 817,211,146 dozens with a money value of $98,000,000. 



PRELIMINARY INVESTIGATIONS. 41 

The foregoing resume" of the present knowledge of the disease gener- 
ally designated as "roup" is important in showing the various condi- 
tions recognized and included under that term. There are other so- 
called fowl diseases, such as influenza and distemper, reported to 
be characterized by somewhat similar symptoms and lesions. Their 
descriptions are so indefinite, however, that it is impossible to differen- 
tiate them from certain forms of the disease more frequently called 
" roup," but which, on account of the nature of the lesious, will be con- 
sidered as diphtheria in this preliminary report. 

I. 

During the past year numerous reports of epizootics among poultry 1 
have been received, and several sick and dead fowls have been sent to 
this laboratory and to the experiment station of this Bureau for exam- 
ination and diagnosis. Certain of the sick fowls improved rapidly 
and soon fully recovered. Others were dead and far advanced in post- 
mortem changes when received, while a few were in a condition more 
suitable for bacteriological and pathological study. 

In all, about 36 fowls came under observation. Several of them 
subsequently recovered; a few died with tumors: in one ease death was 
undoubtedly due to a traumatism; 2 2 died of fowl cholera, and the 
remainder, IS in number, were affected with somewhat similar lesions of 
the mucous membranes of the head, although they came from reported 
epizootics of cholera, diphtheria, and "roup." The examination of 
these fowls revealed the interesting fact that the lesions corresponded 
very closely to those described by Loeffler, 3 Klammer, 4 Babes and 
Puscariu, 5 Eberlin, Loir and Ducloux, 7 and others, as diphtheria in 
pigeons, fowls, and other birds. 

As the disease was not studied in the field it is impossible to define 
the conditions under which it occurred, or to estimate the full extent 
of the loss it occasioned. The fowls examined and here reported came 
from five different flocks, in some of which there is a history of conta- 
gion. Unfortunately, the fowls sent to us were usually among the last 
to be affected. 

The methods employed have varied according to the exigencies of the 

1 In addition to the fowl disease, a similar affection of pigeons, more particularly 
of young squabs, was reported from Waynesboro, Pa., and several of the affected 
birds were sent to this laboratory for examination. The lesions found in these 
birds resemble somewhat closely those found in the mouths of fowls. 

-It is not uncommon to find pieces of wire or nails in the crop and proventriculus. 
In one case, two eight-penny nails and a piece of wire about 2 inches long were 
found piercing the walls of the proventriculus and penetrating the liver and lungs. 

'Mittheiluugen ana dem Kaiserlichen Gesundheitsamte, Bd. II (1884), S. 421. 

4 Berliner thieriirzt. Wocheuschrif't, 1890, No. 18, S. 138. 

ft Zeitschrift f. Hygiene, Bd. VIII (181)0), S. 374. 

fi Monatshefte f. Thierheilkunde. Bd. V (1894), S. 433. 

' Ann. de lTnst. Pasteur, Tome VIII (1894), p. 599. 



42 INFECTIOUS DISEASES AMONG POULTRY. 

different cases. In order, therefore, to present the facts obtained in 
these preliminary studies, it seems best to record somewhat briefly the 
history of each outbreak, so far as determined, together with the notes 
on the individual fowls. 

OUTBREAKS. 



Late in December, 1893, Mr. W., of Middleport, N. Y., sent several 
adult fowls 1 affected with "roup" to the experiment station of this 
Bureau. Mr. W. stated that lie had lost a considerable number of 
fowls from this disease during- the past two or three years. He 
believed that the disease was introduced into his flock by the purchase 
of some choice birds about three years before. Since its first appear- 
ance it had continued to exist in his flock, usually running a chronic 
course, but occasionally breaking out in a more acute and destructive 
form, lie had tried many methods of treatment without success. 

The majority of the fowls sent by Mr. "W. appeared to be well upon 
their arrival at the experiment station. A few of them were killed 
for examination and found to be normal throughout. Five fowls, how- 
ever, were suffering with a slight or more extensive exudate on the 
nasal mucosa, or conjunctiva. These were carefully watched and 
examined from time to time with the results indicated in the appended 
notes. 

Fowl No. 1. — This fowl was suffering from an exudate in the left eye. December 25 
Dr. Smith made several cultures from this exudate. From these two nonpathogenic 
bacilli were isolated. 

December 28: A portion of the exudate was removed from the eye of fowl No. 1 
and inserted beneath the skin, over the abdomen, of a rabbit. On the following day 
there was considerable swelling at the point of inoculation. This continued for sev- 
eral days, when it subsided. The rabbit died February 10, 1894. It was very much 
emaciated, but no bacteria were found in the organs, either in cover-glass prepara- 
tions or in cultures. 

January 25, 1894: Fowl No 1 was found dead; very much emaciated. The left 
eye was covered with a thin layer of a friable, yellowish exudate, composed of 
broken-down cells and bacteria. No fibrin discovered. The nictitating membrane 
thickened; cornea opalescent. The mucosa of the nares, mouth, and pharynx were 
apparently normal. No lesions were found in the internal organs. Culture media 
inoculated with small pieces of the liver remained clear. 

Two white mice were inoculated subcutaneously with bits of the exudate from the 
eye. They died on the fourth and sixth days, respectively, after the inoculation. 

From the organs of the mouse which died on the sixth day a nonmotile bacillus, 
resembling morphologically and in its cultural characters the bacillus of rabbit sep- 
ticaemia, was isolated. Experimental animals inoculated with small quantities of 
culture remained well. This bacillus was carefully studied and retained in subcul- 
tures until the fall of 1894, when a rabbit inoculated intravenously with a moderate 
quantity of pure culture died on the second day with lesions similar to those pro- 
duced by the slightly attenuated bacillus of rabbit septicaemia. 

'The term fowl is used in this article in its restricted sense, referring to GaUus 
domesticus only. This disease, however, is said to affect several other species. 



OUTBREAK I. 43 

The mouse which tlieil on the fourth day exhibited an enlarged ami discolored 
spleen. The other organs were normal in appearance. A cover-glass preparation 
showed it to contain a large number of bacilli. Tubes of agar and bouillon inocu- 
lated with bits of the spleen pulp developed into pure cultures of a motile bacillus, 
which was subsequently found to be possessed of marked pathogenic properties. 
Although fatal to such a large number of experimental animals, experiments to pro- 
duce a disease in fowls similar to the one from which it was obtained gave negative 
results. 

Notwithstanding the marked pathogenesis of this organism, its cultural and physio- 
logical manifestations showed it to be closely related to Bacillus coli commun is, 1 though 
differing from it in several important particulars. 

Fowl No. 2. — January 4, 1894 : This fowl appeared to be well excepting a protu- 
berance beneath the left eye. In order to examine this thoroughly the fowl was 
killed wi'th chloroform. The autopsy showed much emaciation. The protuberance 
consisted of an encysted tumor lying immediately beneath the conjunctiva. It was 
about 2 cm. long and about one-half as thick. Upon section it was found to contain 
a yellowish, caseous substance, which emitted a peculiar, penetrating, and repulsive 
odor. The nasal duct was clear. The eye itself was not visibly affected. The liver 
was unusually fatty. In the left lung were a few hepatized areas. Other organs 
appeared to be normal. 

Cover-glass preparations made from the caseous substance contained many bac- 
teria. Those from the other organs showed no microorganisms. From the caseous 
substance a large number of cultures were made in agar, bouillon, glycerin-agar, 

'On account of the importance of considering all bacteria possessed of pathogenic 
properties, of however slight degree of virulence, the more significant characters 
and properties of this bacillus are appended. 

Morphology. — A small, actively motile bacillus, varying in length from 1.2 to 2 /<, 
ends rounded. It is appreciably larger iu bouillon than in agar cultures. Flagella 
easily demonstrated. Stains readily with the ordinary aniline dyes. 

Culture characters. — On agar it develops in twenty-four hours into a moderately 
vigorous, nioist-appearing, glistening growth of aneutral grayish color. The growth 
is not viscid. When isolated tlie colonies are round, slightly convex, varying from 
1 to 3 mm. in diameter. In gelatin the growth is very feeble in stick cultures. 
After forty-eight to seventy-two hours a delicate grayish growth appears along the 
needle track. The colonies in plate cultures appear on the second day as minute 
grayish points. On potato the day after inoculation at 36° C. a light, lemon-yel- 
low colored growth appears. At the end of from four to six days the growth has 
increased slightly in quantity; the color is somewhat darker. When cultivated in 
peptonized bouillon the fluid becomes heavily clouded in twenty-four hours. After 
about three days a thin, friable, grayish membrane forms over the surface of the 
liquid. The reaction, which at first is faintly alkaline, becomes slightly acid, but 
subsequently strongly alkaline. It does not grow iu acid bouillon. 

The casein of milk is precipitated in from two to three days. It is faintly acid in 
reaction. In about seven days the casein becomes firm and covered with a clear 
serum. 

Its action upon sugars is very constant. Dextrose and lactose are fermented with 
the formation of gas. In both cases 4(3 per cent of the capacity of the closed branch 
of the fermentation tube is filled with gas. The proportion of CO- to the H in the 
gas varies slightly with the two sugars; in the dextrose it is 3:11, in the lactose 
4:11. The production of gas is completed in from three to four days. Fermenta- 
tion tubes containing saccharose bouillon become uniformly clouded throughout, 
strongly alkaline in reaction, but no gas is formed. , 

A marked indol reaction was obtained. 

Pathogenesis. — When isolated this organism was fatal to white mice in from 
twenty-four to forty-eight hours when inoculated subcutaueously with from one to 



44 INFECTIOUS DISEASES AMONG POULTRY. 

gelatin, blood serum, bouillon containing glucose in fermentation tubes, and anaero- 
bic-agar cultures. From these two aerobic bacilli and one streptococcus were iso- 
lated, all of which were harmless for experimental animals. 

Fowls Nos. 3, 4, and 5. — When received these fowls exhibited a very slight quan- 
tity of a mucus-like exudate in the nasal cavities. Thoy were thought at the time 
to be the best cases for an experiment to test the contagiousness of the disease, and 
very soon after their arrival they were penned with six healthy fowls. 

February 21, 1894: About seven weeks later, rabbit No. 144 was inoculated subcu- 
taneously with a loop of the nasal discharge of fowl No. 3. February 23 the rabbit 
was found dead. The autopsy showed a slight purulent infiltration into the subcu- 
taneous tissues at the poiut of inoculation. The spleen was slightly enlarged aud 
of a dark, purplish color. The liver was hypenemic, and the cortex of the kidneys 
deeply reddened, due to injected blood vessels. There were several punctiform hem- 
orrhages beneath the serosa of ileum and lower colon. The lungs were markedly 
emphysematous. Stained cover glass preparations made from the blood, spleen, and 
liver showed innumerable short rod-shaped bacteria with ends rounded, usually 
exhibiting light or uustaiued centers. Pure cultures of this bacillus were obtained 
from the spleen and blood. 

February 24: A second rabbit (No. 145) was inoculated subcutaneously with the 
nasal discharge. It was found dead at 4 p. m. February 25. The autopsy and bac- 
teriological examination revealed the same condition and results as those described 
for rabbit No. 144. 

Fowl No. 3. — February 25 : This fowl was found dead. It was very much emaciated. 
The nasal cavities were occluded with a thick muco-purulent substance. At the 
external nares it had a yellowish color and was dried down into a firm, crust-like 
mass. Throughout the nasal passages to the posterior opening the substance was 
lighter in color and very viscid. The eyes were not affected. The internal organs 
appeared to be normal. Tubes of culture media inoculated from the liver and blood 
remained clear. The fact that two rabbits had been recently inoculated from the 
nasal discharge with like fatal results precluded the necessity of further inocula- 

two drops of a pure bouillon culture. The lesions were characterized by oedema 
about the place of injection, and au enlarged and discolored spleen. Gray mice 
remained well after a similar injection. 

A short series of inoculations were made in white mice, and gray mice succumbed 
to the inoculation with a culture from the spleen of the second white mouse that 
died. The lesion found was a much enlarged spleen as in white mice. 

A guinea-pig inoculated in the abdominal cavity with 0.3 cc. of a bouillon 
culture was found dead on the following morning. The abdominal organs were 
covered with a grayish exudate, which was in the form of shreds over the intestines. 
A few ecchymoses beneath the pleura and peritoneum. The peritoneal exudate 
ontaiued innumerable bacteria. 

Rabbits are not susceptible to subcutaneous or small intravenous injections of 
pure cultures. 

A fowl inoculated in the wing vein with 0.3 cc. of a bouillon culture died on the 
second day. The organs contained very few bacilli. Tubes of culture media inocu- 
lated with bits of the liver developed into pure cultures of this bacillus. 

A fowl inoculated subcutaneously with 0.6 cc of a bouillon culture died in forty- 
four days. No bacteria we-e found in the orgaus and no lesions were discovered. 
The cause of death is questionable. 

A large number of inoculations were made beneath the conjunctiva of fowls, but 
no lesions were produced. Loops of the growth from agar cultures were rubbed 
cover the conjunctiva and into the nasal cavities with negative results. 
i Four fowls were fed with 240 cc. of bouillon cultures of this bacillus mixed with 
a little mill food. They remained perfectly well. 



OUTBREAK II. 45 

tions at this time. The bacillus obtained from rabbits Nos. 144 ami 145 was exceed- 
ingly abundant in the nasal discharge, and especially so in preparations made from 
scrapings of the nasal mucosa. 

Fowl No. 4. — This fowl had presented external appearances similar to those of fowl 
No. 3. 

February 24 : Rabbit No. 97 was inoculated subcutaneously with a loop of the 
na'sal discharge. It was found dead on the following morning. The examination 
showed its organs to contain innumerable bacteria identical with those found in 
rabbits inoculated from fowl No. 3. 

Fowl No. 5. — Like Nos. 3 and 4, this fowl suffered apparently from a nasal catarrh. 
The eyes and mouth were normal. 

February 28: Rabbit No. 149 was inoculated with the nasal discharge. The rab- 
bit died in less than twenty-four hours from septicaemia, the same as the rabbits 
inoculated from fowls Nos. 3 and 4. 

Fowls Nos. 4 and 5 died soon after the inoculations into rabbits were made. They 
were not brought to the laboratory, but examined at the experiment station by Dr. 
F. L. Kilborne, who reported them to be much emaciated and the nasal cavities tilled 
with a muco-purulent substance. The bacteria obtained in pure cultures from the 
rabbits inoculated from fowls Nos. 3, 4, and 5 were carefully studied and compared 
and found to be identical in morphology and cultural characters and to resemble 
the bacillus of rabbit septicaemia. The bacillus obtained from fowl No. 1 was not 
distinguishable from it except in its degree of virulence. »«*J| 

The six fowls penned with fowls Nos. 3, 4, and 5 from the latter part of December, 
1893, until the middle of February, 1894, remained perfectly well. The disease in the 
affected ones remained confined to the nasal cavities. In this experiment all the fowls 
drank from a small basin, and their food was kept in a dish arranged so that they 
were all compelled to eat from it. The disease was not contracted by the exposed 
fowls. 

II. 

In October, 1894, four fowls were received from Mr. W., of Newbern, 
N. C. In an accompanying letter lie stated that they were suffering 
from a disease which was called cholera, and which had killed hundreds 
of fowls about Newbern during the summer and early fall. 

All of the fowls (Nos. 65, 60, 67, and 68) were adults of a mixed breed. 
Upon inspection two of them were found to be apparently well and the 
other two were suffering from an exudate over the conjunctiva of one 
eye and the mucosa of the nasal passages. As this disease was re- 
ported to be contagious it was thought that the apparently well fowls 
(Nos. QG and 67) had simply been exposed, and consequently they were 
kept for a considerable time waiting for the disease to develop. They 
were subsequently chloroformed and carefully examined, but no lesions 
were found in either case, and culture media inoculated with pieces of 
the organs remained clear. 

Fowl No. 65 was chloroformed soon after its arrival and carefully examined. It 
was much emaciated. The left eye was covered with a thick yellowish exudate, 
which was somewhat elastic. The microscopic examination showed small and large 
round cells and bacteria. A fibrin-like substance was present in moderate quanti- 
ties. The exudate was firmly attached to the cornea but not to the conjunctiva 
covering the inside of the lids. The mucosa of the nares and mouth appeared to be 
normal. The intestines were slightly reddened, due to injection of blood vessels. 
They contained a large number of roundworms and several tapeworms attached to the 



46 INFECTIOUS DISEASES AMONG POULTRY. 

mucosa. In the intestinal wall were several nodules. 1 The other organs appeared 
to be normal. 

Tubes of culture media inoculated with the liver remained clear. A tube of agar 
inoculated with the exudate from the eye developed into a pure culture of a motile 
bacillus belonging to the colon group of bacteria. 

Fowl No. 50 was inoculated in both eyes with bits of the exudate from the eye of 
fowl No. 65. The mucosa of the conjunctiva over the lower lids were scraped and 
the exudate thoroughly rubbed into the irritated surface. The inoculation wound 
healed rapidly and the eyes subsequently remained well. 

Fowl No. 68 was chloroformed and examined November 9. Fowl very much emaci- 
ated. The left eye was covered with a cheesy, yellowish, rather hrin exudate, which 
formed a cap over the eye and which was easily removed. It emitted a strong putrid 
odor. The eye was much flattened and the cornea had an opalescent appearance. 
The posterior portion of the eye was normal. The saucer-shaped exudate was 
loosely attached to the conjunctiva over the lids and cornea. There was a small 
amount of firm cheesy exudate in the nasal cavities. The mucosa of the mouth and 
pharynx was normal in appearance. The liver, spleen, kidneys, intestines, and lungs 
also appeared to be normal. Although the fowl was emaciated, it is highly proba- 
ble that the exudate in the eye would soon have sloughed and that recovery would 
have followed. The appearance of the nasal mucosa indicated that the cheesy sub- 
stance in the nasal passages had come from the eye, having coagulated after passing 
through the lachrymal duct. The disease appeared to be localized in the left eye. 

Fowls Nos. 54 and 55 were inoculated by scraping the mucosa of the conjunctiva 
and pharynx and thoroughly rubbing the irritated surface with the exudate from 
the eye of fowl No. 68. The inoculation wound healed and the fowls remained well. 
About ten days later they were reinoculated in a similar manner with the growth 
from an agar culture made from the eye of fowl No. 68. No lesions were produced. 

III. 

In the fall of 1894 several chickens suffering from this disease were 
examined from the flock belonging to Mr. T., who resided near Alexan- 
dria, Va. The insidious nature of certain forms of this malady is well 
illustrated by this outbreak. Several healthy young chickens were 
desired for experimental purposes, and Mr. T. reported that he possessed 
some very thrifty chickens of the desired age, and his account of the 
history of his fowls showed that the place had been free from fowl dis- 
eases for several years. Nine of the chickens were secured and placed 
on the experiment station. A few days later two of them were brought 
to the laboratory, where, upon inspection prior to their use, they were 
found to be suffering with an exudate which covered the greater part 
of the mucosa of the mouth and pharynx. The other seven chickens 
were examined by Dr. Schroeder, director of the station, who found a 
few of them to be similarly affected. The remainder appeared to be well, 
but were subsequently attacked. Some of these were allowed to die, 
and others were killed in the earlier stages of the disease for exam- 

1 During the summer of 1894 numerous fowls were found to be affected with a 
disease of the intestines, due to the presence of tapeworms. This disease is espe- 
cially interesting, owing to the resemblance of its lesions to those of tuberculosis. 
I have described it somewhat fully in an article entitled "A Nodular Ta^uiasis of 
Chickens," to appear in a forthcoming report of this Bureau, 



OUTBREAK III. 47 

ination. Mr. T. states that later in the fall lie lost a few chickens 
from this disease, and a large number were affected which recovered. 

Fowl No. 60 was brought to the laboratory October 17. On the following day it 
was found sitting in a crouched position, feathers ruffled, and the head drawn close 
to the body. It breathed through the mouth. The eyes were usually closed; no 
exudate on the conj unctiva ; temperatu re 108° F. The symptoms apparently improved 
during the next few clays, but on the morning of October 22 it was found dead. 
This chicken was about 2 months old and was much emaciated. Ou the lower 
side of the cornea of the right eye there was an area about 2 by 1 mm. covered with 
a grayish exudate loosely attached to the cornea. The mucosa over the entire left 
side of the mouth was covered with a yellowish exudate one-fourth to 24 mm. in 
thickness. It was easily removed and exceedingly friable. The mucosa of the 
pharynx, larynx, and nares was normal. The internal organs appeared to be nor- 
mal. CuTtures made from the exudate, liver, and kidneys contained a variety of 
bacteria, which, however, were not isolated and studied in pure culture. 

Fowl No. 59 was received at the laboratory at the same time, and it manifested 
symptoms similar to those described for No. 60. After a few days the symptoms 
showed a general improvement, which continued until October 20, when it was 
chloroformed for examination. 

The autopsy showed the fowl to be very much emaciated. The mucosa of the 
nares and the conjunctiva was normal. On the floor of the mouth, on each side of 
the tongue and extending back on either side of the larynx, there was a band of 
grayish exudate about 2 mm. in width, firmly adhering to the mucosa. In micro- 
scopic section the exudate was found to be composed for the greater part of round 
cells and bacteria. (See PI. VI, fig. 3.) 

The internal organs were normal in appearance. Tubes of agar inoculated with 
bits of the liver and kidney developed into cultures containing several forms of bac- 
teria, including a micrococcus frequently encountered and Bacillus coli communis. 

A guinea-pig was inoculated subcutaneously with a small piece of the exudate, 
including subjacent muscle. A small swelling developed at the place of inoculation. 
Five days after inoculation the guinea-pig was chloroformed and examined. At the 
place of injection the subcutis was infiltrated with a pasty, purulent substance over 
an area of 5 by 3 cm. The adjacent muscle necrosed. Thoracic and abdominal 
organs normal in appearance. No bacteria were found in cover-glass preparations 
and subsequently in cultures made from the organs. The pus in the local abscess 
contained innumerable bacteria, apparently of the same species. Bouillon and agar 
inoculated from the infiltrated substance developed iuto pure cultures of a nonmotile 
bacillus, which was carefully studied and found to be similar in its pathogenesis and 
cultural characters to that of slightly attenuated rabbit septicaemia. 

Fowl No. 69. — In the latter part of October this fowl was attacked, and a thick 
exudate formed on the larynx. November 2 it was chloroformed. The eyes were 
covered with exudate which agglutinated the lids. Upon opening the lids the exu- 
date was easily removed from the conjunctiva covering the lids, but it was firmly 
attached to the cornea. The exudate formed saucer-shaped caps which covered the 
eyes, being 2 mm. thick over the cornea, gradually thinning out to a sharp margin. 
About the margin of the firm exudate was a small quantity of partially coagulated 
mucous substance. The mucosa of nares normal. On both the anterior and poste- 
rior sides of the laryngeal opening there was an area about 3 mm. in width covered 
with a grayish exudate adhering firmly to the mucosa. It was removed with diffi- 
culty, leaving a raw surface. The kidneys were mottled with grayish lines, due to 
large quantities of urates in certain of the tubules. Other organs appeared to be 
normal. 

November 2 : Rabbit No. 215 was inoculated subcutaneously with a small quantity 
of the coagulated mucus from fhe eyes, 



48 INFECTIOUS DISEASES AMONG POULTRY. 

Novembero: Rabbit found dead this morning. At the point of inoculation the 
s'ubcutis was infiltrated with a purulent substance over an area 2 by 5 cm. The 
pleura over the lungs and parietes was covered with a thin cellular exudate. 
Lungs hypertonic. Spleen much enlarged and dark colored. Kidneys hyperajinic. 
The liver mottled with areas covered with a delicate grayish exudate. The mucosa 
of the lower colon sprinkled with punctiform hemorrhages. Cover-glass prepara- 
tions from the organs contained innumerable short bacilli with ends rounded. Pola- 
stain not marked. 

Rabbit No. 225 was inoculated with 0.3 cc. of a bouillon culture obtained from the 
spleen of rabbit No. 215. It was found dead on the fourth day with lesions similar 
to those found in rabbit No. 215. Stained cover-glass preparations made from the 
liver and spleen contained innumerable polar-stained bacteria. Pure cultures or 
this organism were obtained from the liver. A guinea-pig inoculated into the abdom- 
inal cavity with 0.3 cc. of a bouillon culture from rabbit 215 died within twenty 
four hours. A subcutaneous inoculation with a similar quantity produced death in 
six days. 

Fowl Xo. 70 was received at the same time as No. 69 and chloroformed for exami- 
nation. Much emaciated. The left eye was closed, the lids agglutinated together; 
tho eye was covered with a yellowish cheesy exudate adhering quite firmly to the 
cornea. It gave off a disagreeable odor. The exudate had sloughed from the con- 
junctiva of the lids. In the nasal passages there was a small amount of cheesy exu- 
date. Mucosa of mouth normal. The internal organs appeared to be normal. No 
cultures were made. 

Fowl Xo. 71 was found dead November 5. This fowl was much emaciated. Tho 
left conjunctival sac contained considerable semiliquid substance. The mucosa 
was slightly reddened and the cornea had an opalescent appearance. No other 
lesions were found. Cultures made from the exudate iu the eye contained several 
forms of micrococci and a short nonmotile bacillus. 

Rabbit No. 223 inoculated subcutaneously with the liquid from the eye. 

November 12 the rabbit was found dead. The autopsy showed extensive purulent 
infiltration into the subcutaneous tissue about the point of inoculation. The tho- 
racic and abdominal organs were covered with a thin grayish exudate composed of 
cells and bacteria. Spleen enlarged; pulp soft. No bacteria were found in cover- 
glass preparations from the organs, but in those from the exudate there were innumer- 
able short bacilli with ends rounded, frequently exhibiting a polar*stain. Pure cul- 
tures of this bacillus were obtained from the spleen and liver. 

November 14: Fowl No. 64 was inoculated in the conjunctiva with 0.2 cc. of a 
bouillon culture of the bacillus obtained from fowl No. 71. On the following day 
there was much swelling of the eyelid. The swelling increased, with accompanying 
reddening, for about two days, when it began to subside and finally entirely disap- 
peared. The fowl continued well. 

November 14: Fowl No. 65 (previously inoculated on the mucosa of head) was 
inoculated in the wing vein with 0.3 cc. of a fresh bouillon culture of this bacillus. 
The fowl remained well. 

Two small chickens were inoculated beneath the mucosa of the mouth and also 
the conjunctiva with several drops of a pure culture of this bacillus without pro- 
ducing any appreciable effect. 

Fowl Xo. 72 was found dead November 7. It was much emaciated. A thin gray- 
ish substance covered the cornea from which a nonpathogenic bacillus was iso- 
lated. No lesions could be found, and culture media inoculated from the organs 
remained clear. 

Fowl Xo. 73 was found dead November 9. It was much emaciated. The conjunctiva 
and mucosa of the nares were normal. The roof of the mouth and the pharynx 
were covered with a thick grayish exudate, which was removed with difficulty, leav- 
ing a raw surface. The entire tongue was surrounded with a thick exudate, which 



OUTBREAK IV. 49 

was easily removed. The examination of sections allowed a eel] infiltration extend* 
ing through the mucosa into the subjacent muscles. No other Lesions were found. 
Ou account of a scarcity of rabbits no inoculations were; made from this fowl. 

Fowl No. 75 was found dead November 22. Fowl considerably emaciated. The left 
eye was covered with a thick necrotic exudate, which was easily removed from both 
the eye and conjunctiva of the lid. The exudate extended through the nasal duct 
into the nares, In the posterior nares the exudate was bordered by a layer of a, gray- 
ish, mucus-like substance. Small areas on the roof of the mouth and about the 
glottis were covered with a grayish, firmly-adhering exudate, which left a raw 
surface upon removal. No other lesion discovered. 

November 22: Rabbit No. 226 inoculated subcutaueously with the mucus-like 
substance from the nares. 

November 23: Rabbit found dead this morning. Owing to the large amount of 
exudate injected beneath the skin the local lesion was unusually severe. The 
abdominal viscera were hypeneinic. Cover-glass preparations made from the organs 
contained many elongated bacteria. A pure culture of a nonmotile bacillus was 
obtained from the liver. A rabbit inoculated subeutaneously with 0.3 cc. of this 
culture died of septica'inia in less than twenty-four hours. This bacillus was iden- 
tical in its morphology and cultural characters with those obtained from fowls Nos. 
59, 69, and 71. 

IV. 

Ill October, 1894, a severe epizootic was reported to have occurred 
among fowls belonging to Mr. P., residing on Bemiiugs road, in the 
District of Columbia. Mr. P. stated that a considerable number of bis 
fowls bad died from what he thought to be diphtheria, on account of 
the grayish membrane observed on the mucosa of the mouth and 
pharynx. Unfortunately, he did not notify us of this disease until it 
was nearly over, so that we had an opportunity of examining only the 
three last fowls affected. Two of these were not received until some 
time after death, and the other died on the third day after its arrival. 
The results of these examinations are appended: 

Fowl No. 5S. — This fowl was received at the experiment station October 9. It was 
found dead on the morning of October 12. Fowl very much emaciated. The mucosa 
of nares, mouth, and pharynx appeared to bo normal. No lesious were found in the 
internal organs excepting a few nodules due to certain forms of tapeworms in the 
intestine. Cover-glass preparations of the blood and liver showed no bacteria. In 
those from the kidney a very few short bacilli with rounded ends were observed. 
Tubes of bouillon were inoculated with bits of the blood, liver, and kidney. The 
tubes inoculated with the blood and liver developed into impure cultures of ordinary 
saprophytic bacteria. The culturofrom the kidney contained a short motile bacillus 
belonging to the colon group. 

Fowl No. 61. — A small chicken, about 10 weeks old. It had been dead about 
twenty-four hours when received. Much emaciated. Along the cleft in the hard 
palate there was a narrow strip covered with a thick grayish exudate, which was 
firmly adherent to the mucosa. On the posterior surface of the pharynx and also 
about the glottis were small areas covered with a similar exudate. The left eye was 
covered with a firm, yellowish mass of necrotic exudate, which was easily removed. 
The color of the internal organs was slightly altered, due to post-mortem changes ; 
otherwise they appeared to be normal. 

A guinea-pig was inoculated subeutaneously with a bit of the exudate, including 
the subjacent tissue from the roof of the mouth. A slight swelling occurred at the 
point of inoculation. Four days after the inoculation the guinea-pig was ehloro- 
17897— No. 8 4 



50 INFECTIOUS DISEASES AMONG POULTRY. 

formed and culture media inoculated from the local lesion. These developed into 
pure cultures of a motile bacillus belonging to the colon group. 

Fowl Xo. 62. — This fowl was received at the same time as No. 61. The lesions were 
confined to the nasal passages, which were occluded with a yellowish cheesy sub- 
stance, and the left eye, which was covered with a quite firm, easily removable 
necrotic exudate. The conjunctiva of the lids were not appreciably affected. The 
cornea was opaque. 

A guinea-pig was inoculated with a portion of the exudate from the nasal cavities. 
It was chloroformed six days later for examination. The subcutaneous tissue about 
the point of inoculation was infiltrated with a purulent substance over an area of 
about 1 cm. in diameter. No other lesions. From the local lesions pure cultures 
of a motile bacillus belonging to the colon group were obtained. 

V. 

This outbreak occurred among the fowls belonging to Mr. H., who 
resides at Brookland, D. C. He states that he had about 75 fowls, all 
of which were in excellent condition up to the purchase of a cock, which 
was subsequently found to be diseased. A large number of his fowls 
became infected. They usually recovered, although several of the badly 
affected ones were killed. Late in October Mr. II. brought a hen which 
was suffering from the disease to this laboratory. This was one of the 
last of his fowls to be attacked. At the time it came under my observa- 
tion the disease was confined to the left eye and an area of firmly attached 
exudate on the roof of the mouth. This fowl was kept under observation 
for several weeks, and cultures and animal inoculations were made from 
the exudate as indicated in the appended notes. 

Fowl Xo. OS. — Received October 20. The left eve was considerably swollen, the two 
lids being agglutinated together. The cornea had an opalescent appearance. Res- 
piration apparently normal. Temperature 107° F. Fowl sits with the head drawn 
close to the body. Tubes of agar and bouillon inoculated with the exudate developed 
into pure cultures of a nonpathogenic micrococcus. 

A white mouse was inoculated subcutaneously with a loop of the exudate from the 
eye. It remained well for about three weeks, when it died. As it was badly decom- 
posed when examined no cultures were made. 

Fowl Xo. 04 Avas again inoculated in both eyes with the exudate from the eye of 
this fowl. The exudate was thoroughly rubbed on the conjunctiva. Four days later 
the inoculation was repeated. The eyes remained apparently perfectly well. 

October 22: A guinea-pig was inoculated into the abdominal cavity with 0.4 cc. of 
a bouillon culture from the eye exudate. It remained well. 

October 24: The left eye of fowl No. 63 was covered with a quite firm, nearly 
white exudate, which causes it to protrude considerably. The lids were firmly agglu- 
tinated together, being separated with much difficulty. The lid was lined with a 
thick, quite firm, whitish exudate. Nictitating membrane much thickened. There 
were several areas of a grayish exudate in the roof of the mouth. Cultures in agar 
and bouillon made from the eye contained two species of micrococci. The growth 
in the agar consisted of a few colonies only. 

A whitemouse inoculated with the exudate was found dead on the third day. From 
the liver a culture of a micrococcus was obtained. This organism did not prove 
fatal in subsequent inoculations. 

October 27 the eye was entirely closed. The agglutinated lids were separated and 
a wedge-shaped mass of necrotic exudate was easily removed. This covered the 
entire inner surface of the lower lid, being thicker at the exposed or free margin. 



VARIETIES OF LESIONS. 51 

In section it was found to be composed very largely of broken-down cells. The 
cornea bad an opalescent appearance and was decidedly flattened. A nonpatho- 
genic bacillus was obtained in agar cultures from the eye. 

November 9, the fowl appeared to be improved. The eye was covered with a 
yellowish exudate which emitted a peculiar, offensive odor. It was easily removed 
leaving a roughened, nearly healed surface. The cornea was opaque and depressed. 
The exudate from the mucosa of the mouth had sloughed, leaving a healed surface. 

The fowl was chloroformed for further examination. It was ranch emaciated. 
The internal organs appeared to be normal. Tubes of bouillon inoculated from the 
liver, spleen, and blood remained clear. 

II. 

A review of the disease found in the 18 fowls shows that while there 
are many dissimilarities in the lesions in the different fowls they can not 
be easily construed to represent different diseases. Although much of 
the confusion which characterizes the popular conception of " roup" is 
apparent in the fragmentary history obtained of the outbreaks, a more 
careful study of the individual eases will show that there is a striking- 
similarity between them. The lesions in the fowls examined were for 
the greater part localized on the mucosa of the organs in the head. 
Although all of the fowls which died were much emaciated, there were, 
with few exceptions, no lesions or evidence of organic disease in the 
internal organs. The cause of death and the extreme emaciation is 
difficult to explain in those cases where the lesions were confined to 
one eye or to the mucosa of the nares, excepting on the supposition 
that some poisonous or toxic substance was absorbed from the seat of 
the disease. In those cases where the lesions were in both eyes, or in 
the mouth and throat, difficulty in finding or swallowing food affords a 
rational explanation. 

A study of the lesions revealed the interesting fact that in some cases 
the exudate was of a croupous character, and in others of a diphtheritic 
nature. In a considerable number of the fowls the exudate was more or 
less sloughed from the underlying tissue. The hypothesis is suggested 
by these varied conditions that perhaps the apparent croupous exudate 
is the first stage of the diphtheritic condition, and that the sloughed 
mass of decomposing exudate so frequently found is the last or advanced 
stage. 1 here is a certain amount of evidence to support such an hypoth- 
esis, both in the description of fowl diphtheria in Europe and in the 
cases here recorded. The three singes or varieties of lesions which 
represent the types of this disease as encountered in these investiga- 
tions may be more definitely defined as follows: 

(1) An exudate of a serous or mucopurulent character in the conjunc- 
tiva or nasal cavities. Ordinarily this condition can not be recognized 
in the mouth. The mucosa in these eases is apparently but slightly 
altered. (Fowls Nos. 3, 4, 5, Outbreak I, and No. 71, Outbreak III.) 

(2) The mucosa over a small or larger area is covered with a spread- 
ing exudate of a grayish or yellow color. It is firmly attached to the 



52 INFECTIOUS DISEASES AMONG POULTRY. 

mucous membrane, and when removed leaves a raw, bleeding surface. 
Sections through this exudate and the subjacent tissues show that the 
epithelial layer is destroyed, and the underlying tissue infiltrated 
with cells. The extent of the infiltration varies in different individuals. 
(Fowl 59, Outbreak I.) 

(3) The mucosa is covered with a thick mass of exudate, varying in 
color from a milky white to a lemon yellow or brown. It is easily 
removed, leaving a more or less granular and healed surface. This 
sloughed mass is frequently dried at its margins to the adjacent tissue. 
It emits a strong putrid odor, due to decomposition. The drying of the 
margins prevents the fowl from expelling the exudate after it becomes 
separated from the underlying tissue. (Fowl 63, Outbreak V.) 

The evidence to support the supposition that the three forms or types 
of exudate described are different stages in the same morbid process, 
as gathered from the post-mortem notes and bacteriological study of the 
cases here reported, may be summarized as follows: 

(a) Abnormal conditions, representing the intermediate and con- 
necting links between the specific types of lesions, were frequently 
encountered. 

(b) Although but one form of exudate was usually present in a single 
fowl, there were marked exceptions, in which two, and in one case the 
three, forms were coincident. Thus in fowl No. 75 (Outbreak III) the 
eye was covered with a sloughed exudate. In the posterior nares there 
was a layer of mucopurulent substance, and on the mucosa of the 
mouth were areas of a diphtheritic exudate. Fowls Nos. 69 and 73 
furnish examples where the diphtheritic process and the sloughed exu- 
dates were present. 

(c) The same species of a pathogenic bacillus was associated with 
each form of exudate. It was almost invariably found with the first 
and second, but rarely with the third. 

In the fowls which died, the exudates were for the greater part in the 
advanced stage, although there were several fatal cases in which the 
lesions were restricted to an abnormal quantity of a serous or muco- 
purulent, more or less viscid, exudate in the conjunctiva or nasal cavi- 
ties. The best illustration of the diphtheritic process was found in 
certain of the fowls killed for examination. 

The distribution of the lesions shows that the conjunctiva was most 
frequently affected. The exudate in the nasal cavities was in a few 
cases undoubtedly the result of the coagulation of the liquid which had 
passed during the course of the first stage from the conjunctiva through 
the lachrymal duct into the nares. In certain of the other cases, how 
ever, the lesions appeared in the nares only (fowls Nos. 3, 4, and 5). 
Inadvertently, in these cases no material for sectioning was saved from 
the mucosa of the nares or conjunctiva. Sections of the exudate, with 
subjacent tissue from the cornea and the mouth, show that there is a cell 



BACTERIA ASSOCIATED WITH THE LESIONS. 53 

infiltration into the mucosa which destroys the epithelial layer and 
frequently the submucous tissues to a considerable depth. (See PI. VI.) 

The fact should not be overlooked, as pointed out in the post-mortem 
notes, that the disease in the eye was confined to the conjunctiva and the 
cornea, the posterior portion remaining - apparently normal. Although 
the lesions were found more frequently in the eye, the number of fowls 
examined was not large enough to admit of the conclusion that this is 
generally the case. 

From the observations thus far made the provisional theory is enter- 
tained that the three forms of the exudate — serous or mucopurulent, 
diphtheritic, and sloughed mass — represent three stages in the course of 
the same disease. It is easily understood that fowls examined in the 
first stage would be said to be affected with a catarrhal condition of the 
mucosa of the eyes or nares. It is highly probable that in many cases 
the disease never reaches the second stage (see fowls Nos. 3, 4, 5, and 
71), and if these cases alone were examined the diphtheritic condition 
would not be suspected. It appears, however, that in the majority of 
cases the disease runs its course, and membranes are formed, slough, 
and recovery follows. It is further presumable that the disease in 
question appears sometimes in a virulent and destructive form. I am 
iu possession of statements from poultry raisers which show that there 
are occasionally epizootics of a disease characterized by exudates in 
the eyes, nose, or mouth, which runs a rapidly fatal course. It appears 
that it is such outbreaks which have been reported in Europe as diph- 
theria, and not the low form of chronic disease which I have encountered. 

It is highly probable that there are many affections of fowls resembling 
somewhat closely the lesions found in the cases examined which are 
etiologically different. There is much doubt respecting the cause of 
the apparently sporadic cases of this disease. Whether they differ 
other than in the degree of virulence of the specific organism from the 
rapidly fatal disease sometimes reported can not be determined until 
such epizootics can be thoroughly studied. It is hoped that the investi- 
gation of this disease or class of diseases may be continued until the 
doubtful points concerning their nature and cause are clearly explained, 
and efficient methods of prevention and treatment are determined. 

BACTERIA ASSOCIATED WITH THE LESIONS. 

It has already been shown that bacteria were not found in the internal 
organs or blood of the affected fowls when they were examined before 
post-mortem changes occurred. It lias also been stated that a non- 
motile, pathogenic bacillus was found associated with the lesions, espe- 
cially in the first and second stages, in a considerable number of the 
fowls. 

The examination of the exudates for bacteria was attended with 
many difficulties, owing to the presence of a large number of sapro- 



54 INFECTIOUS DISEASES AMONG POULTRY. 

pliytes. 1 The method found to be the most trustworthy for the isola^ 
tion of the pathogenic bacteria was the subcutaneous inoculation of 
experimental animals with the exudates. If the inoculated animals 
died, pure cultures of the pathogenic organism were obtained from the 
blood, liver, or spleen. If they survived, they were subsequently chloro- 
formed and cultures of the parasitic bacteria obtained from the tissue 
at the point of inoculation. 2 By this process the saprophytes were 
destroyed in the tissues and only those organisms encountered which 
were suspected to be of more or less etiological importance. 

The success of the animal inoculation over the culture methods in iso- 
lating the nonmotile pathogenic bacillus is explained from the fact that 
it is not vigorous in its growth on culture media and that it was ordina- 
rily crowded out by more vigorously growing saprophytes. It isfurther 
presumable that in the older exudates its virulence is gradually lost 
(see fowls Nos. 1 and 59), so that its presence could not be detected 
readily by animal inoculation. If rabbits had been inoculated, however, 
with large quantities of the exudate from the more advanced disease a 
few additional cases containing the pathogenic — but attenuated — bacil- 
lus would undoubtedly have been found. The severe local lesions pro- 
duced in rabbits by the injection of such material caused them, with 
few exceptions, to be abandoned. It is evident, in view of the results 
obtained, that rabbits were the most efficient experimental animals to 
use in this work, and that fowls were the most refractory. The scarcity 
of rabbits, however, led to the use of other animals in a few cases. 

Cover-glass x> reparations made from the lesions of the affected fowls 
were carefully stained and examined. 3 Those prepared from the surface 
of the exudate and from the necrotic masses generally contained innu- 
merable bacteria, but no predominating species was observed. Similar 
preparations from the base of the exudate in the more recent stages con- 
tained a large number of short bacilli with the ends rounded. These 
forms frequently exhibited a polar stain. Several preparations were 

'A large number of species of bacteria were isolated and studied somewhat 
carefully. Among them are several quite interesting forms, some of which were 
suspected to be of more or less economic importance. Prominent among these was a 
bacillus which resembled morphologically and in certain of its cultural characters 
the bacillus of tuberculosis. It was not pathogenic for guinea-pigs or fowls, and 
did not take the Koch stain. 

2 It is of interest to note that several varieties of colon bacteria were isolated in 
this way. One of tbese possessed such variations from the colon bacillus in its cul- 
tural manifestations and it was possessed of such marked pathogenesis that for a 
time it was suspected of bearing some causal relation to the disease. It was briefly 
described in a footnote on page 43. 

3 In both fresh and stained preparations a long spirillum was found to be quite 
abundant. It was from 2 to 4 11 in length. Thus far I have been unable to detect it in 
artificial cultivations. 



SUMMARY OF INOCULATIONS. 



.55 



stained for tubercle bacilli, but with negative results. A summary of 
the results obtained from animal inoculations is appended in tabulated 
form 

Animals inoculated with the exudate from affected fowls. 



Animals 
inoculated. 



Inoculated with 
exudate front- 



Date of 
inoculation. 



Results. 



Remarks. 



Rabbit No. 117... Eye, fowl No. 1 Dec. 28,1893 



White mouse. 



Do 

Rabbit No. 144. 

Rabl.it No. 145. 
Rabbit No. 97.. 
Rabbit No. 149. 
Guinea-pig 222. 

Guinea-pig 223. 

Guinea-pig 209. 



Fowl No. 50.... 

Fowl No. 54 

Fowl No. 55.... 
Rabbit No. 215. 



Rabbit No. 223... 



Rabbit No. 226.. 



.do i Jan. 23,1894 



do 

Nares, fowl No. 3 . 

do 

Nans, fowl No. 4. . 
Nans, fowl No. 5. . 
Mouth, fowl No. 61. 

Nares, fowl No. 62. 

Mouth, fowl No. 59. 



Eve, fowl No. 65. 
E've, fowl No. 68. 

. .'..do 

Eye, fowl No. 69. 



Eyes, fowl No. 71.. 
Nares, fowl No. 75. 



do 

Feb. 4, 1894 

Feb. 24, 1894 

do 

Feb. 29, 1894 
Oct. 9, 1894 

do 

Oct. 20,1894 



Oct. 24,1894 
Oct. 27,1894 
do 

Nov. 2,1894 



Nov. 5,1894 



Nov. 22, 1894 



Died Feb. 10,1894 

Died Jan. 27, 1894.. 

J Heel. Jan. 29. 1894.. 

Died Feb. 28, 1894. 

Died Feb. 25.1894. 

do 

Died Mar. 1,1894.. 
Chloroformed Oct. 

13, 1894. 
Chloroformed Oct. 

15, 18114. 
Chloroformed Oct. 

25, 1894. 

Remained well 

do 

...do 

Found dead Nov. 
5, 1894. 

Found dead Dec. 
19, 1894. 

Found dead Nov. 
23, 1894. 



Rabbit very much emaci- 
ated ; no bacteria found 
in its organs. 
Enlarged and discolored 
spleen; a pathogenic inu- 
tile bacillus. 
Spleen enlarged; nonmo- 
tile pathogenic bacillus. 
Septicaemia; nonmol ile 
pathogenic bacillus. 
Do. 
Do. 
Do. 
Local lesion contained l',a- 

dlluS COli ro)u in unit. 

Do. 

Local lesion contained non- 
motile pathogenic bacil- 
lus. 

No local reaction. 
Do. 
Do. 

Plenritis; hemorrhages in 
the intestines; nonmo- 
tile pathogenic bacillus. 

Pleuritis and peritonitis; 
nonmotile pathogenic 
bacillus. 

Septicaemia; nonmotile 
pathogenic bacillus. 



The table shows that the pathogenic bacillus was obtained from the 
lesions of fowls Nos. 1, 3, 4, 5, 59, 69, 71, and 75, or nearly 50 per cent of 
those examined. It is a significant fact that the bacillus was obtained 
from all the fowls but one (No. 61) where the lesions either in the 
eye, nares, or mouth were not far advanced. In one case (No. 73) no 
inoculations were made. The almost constant appearance of this bacil- 
lus in the more recent lesions renders the apparent small percentage of 
cases from which it was isolated of much greater importance than it 
would at first be considered. A comparative study of the bacteria from 
the different fowls showed that those obtained from fowls JSos. 1, 59, 69, 
and 71 were attenuated in varying degrees, while those from the other 
cases were sufficiently virulent to destroy rabbits within twenty-four 
hours. This variation in the degree of virulence of the cultures obtained 
from different fowls is interesting and important. There was no differ- 
ence in their cultural characters. A glance at the post-mortem notes 
will show that in the fowls from which the attenuated forms were 
obtained the lesions were apparently older or more advanced than in 
the other cases. 

In previous investigations ' rabbits were inoculated with the nasal 
and pharyngeal secretions of several healthy fowls. These rabbits 



1 Bulletin No. 3, Bureau of Animal Industry, 1893, p. 47. 



56 INFECTIOUS DISEASES AMONG POULTRY. 

remained perfectly well. Although septic bacteria are known to be 
common in the secretions covering the normal mucosa of the upper air 
passages of several species of domesticated animals, such organisms 
have not been reported from the mucosa of healthy fowls. 

In 1890 two fowls 1 which died very suddenly at the experiment sta- 
tion of this Bureau were examined. One of them exhibited a croupous 
exudate extending from the larynx into the trachea, and the other a 
swollen condition of the mucosa of the mouth and oesophagus. No 
pathogenic bacteria were obtained from the fowl suffering from the exu- 
date, but from the other were obtained pure cultures of a bacillus not 
distinguishable from that of swine plague. 

It is impossible to positively identify the pathogenic bacillus found 
associated with the lesions in this disease with the one described by 
European writers as the cause of fowl diphtheria. Morphologically it 
is similar to the one described by Loefrler, but its pathogenesis is differ- 
ent. This may be due, however, to difference in the degree of virulence. 
There is much obscurity in the reference to the properties of the bacilli 
found by other investigators as the probable cause of diphtheritic affec- 
tions of fowls and birds, as their descriptions are exceedingly meager, 
being often limited to the morphology and possibly the character of the 
growth on one or two of the more commonly used culture media. 

In those species of pathogenic bacteria which have been more fully 
described a more accurate comparison is possible. Thus, the bacilli of 
fowl cholera, swine plague, and rabbit septicaemia are found to be com- 
parable with the bacillus about to be described, and found in the lesions 
of this disease of fowls. While it is not my purpose to discuss at this 
time the identity or relationship of these bacteria, it is important to 
know that a bacillus associated with the peculiar lesions of this disease 
should be so similar to the one described by European writers as the 
cause of fowl cholera. The more essential properties of the bacillus 
found, apparently the etiological factor, in the lesions of the diphtheritic 
disease of poultry which I have studied are appended : 

DESCRIPTION OF THE NONMOTILE PATHOGENIC BACILLUS. 

Morphology. — A nonruotile, rod-shaped organism 0.8 to 1.5 ju long and from 0.8 to 
1.2 /.i thick. The ends are oval, and the shorter forms appear to be nearly spherical. 
In bouillon they are frequently in short chains and in clumps. When stained with 
the aniline dyes in cover-glass preparations made directly from animal tissues they 
exhibit a light center, occasionally showing deeply stained poles. In preparations 
from cultures this character is much less marked. No capsule has been positively 
demonstrated, although certain preparations suggest its existence. It stains readily 
with the aniline dyes ordinarily used. It does not retain the coloring matter when 
treated after the Gram method. 

Culture characters. — On agar at 36° C. the growth is not vigorous. It is of a neu- 
tral gray color, with a glistening, moist-appearing surface. The growth is slightly 
viscid, and adheres quite firmly to the agar surface. The condensation water becomes 

1 Special Report on Swine Plague, Bureau of Animal Industry, Department of Agri- 
culture, 1891, p. 158. 



DESCRIPTION OF THE BACILLUS. 57 

faintly clouded. Within agar the colonies appear as minute grayish dots. The 
growth is completed in about forty-eight hours. In agar plates (double disks) it 
emits a disagreeable, pungent odor, similar to that observed in cultures of the 
swine-plague bacillus. 

It does not grow in alkaline, peptone gelatin. It does not develop on potato. 

Milk remains unchanged in appearance for six weeks. Cultures which had grown 
for several days were boiled. No change was produced. 

Alkaline bouillon at 36° C. becomes uniformly clouded in twenty-four hours. The 
reaction becomes acid in from one to two days. It docs not grow in acid bouillon. 

In bouillon containing sugar the growth was slightly more vigorous. In the fer- 
mentation tubes the liquid in both branches becomes cloudy, (ias is not produced. 
In bouillon containing dextrose and saccharose the alkaline reaction is changed to a 
strongly acid one in twenty-four hours ; the bouillon containing lactose remained 
alkaline. 

In a weak solution of peptone containing salt it grew feebly, but gave a decided 
indol reaction. The phenol reaction was not detected. 

Thermal death point. — This organism is destroyed in bouillon cultures heated in a 
water bath for live minutes at 58 J C. Au exposure of ten minutes to a temperature 
of 54° C. was not fatal. 

Effect of drying. — The bacillus is destroyed in twenty-four hours by drying on 
cover-glasses at the temperature of the laboratory. 

Effect of low temperature. — Dry cover-glass preparations were exposed in a sterile 
test tube to a temperature varying from zero to a few degrees above tor a period of 
seventeen hours. At the end of that time they were placed in tubes of bouillon and 
put in the incubator. These tubes contained pure cultures of this bacillus on the 
following day. 

Disinfectants. — A few preliminary tests showed that this organism was very sensi- 
tive to ordinary disinfectants. To determine more accurately the streugth of the 
solution and the time necessary for a fatal exposure, Dr. C. F. Dawson kindly car- 
ried out an extensive series of experiments, the more important results of which are 
appended : 

Commercial sulphuric acid in one-eighth of 1 per cent solution destroys in thirty 
minutes; in one-fourth of 1 percent it kills in ten minutes. 

Lime water destroys the organism in one minute. When diluted four times (0.015 
per cent lime) it requires thirty minutes. Carbolic, acid in strengths of 0.5, 1, and 2 
per cent destroys this bacillus in sixty, five, and one minutes, respectively. 

The frequency with which sulphur fumes are used to disinfect chicken houses led 
to the testing of their efficiency on this organism. The methods and results reported 
by Dr. Dawson are as follows : 

"A drop of bouillon culture was placed upon a sterile cover-glass inside a large 
glass jar which had been specially prepared for the test. About a half teaspoonfiil 
of sulphur was placed upon a sheet of asbestus and ignited. The lid of the, jar was 
put on and in a short time the jar was filled with the white fumes. In three hours 
the cover-glasses were carefully removed and dropped into a tube of sterile bouillon 
and placed in an incubator. They invariably remained clear." 

Pathogenesis. — Rabbits inoculated subcutaneously with 0.1 cc. of the virulent 
bouillon cultures died in from eighteen to thirty-six hours with lesions similar to 
those produced by swine-plague bacteria of a virulent type. The organs contained 
large numbers of oval bacteria exhibiting a polar arrangement of the protoplasm. 
Those inoculated in a similar manner with the attenuated bacilli lived several days. 
They exhibited more or less severe local lesions and exudates on one or more of the 
serous membranes. Adult fowls inoculated subcutaneously with 0.5 cc. of a fresh 
bouillon culture of the virulent form remained well. A young fowl (about 6 weeks 
old) inoculated in a similar manner with 0.3 cc. died on the fourth day. The kid- 
neys were abnormally yellow in color and contained large quantities of urates. 



58 INFECTIOUS DISEASES AMONG POULTRY. 

Other organs were apparently normal. No bacteria were found in cover-glass prepa- 
rations from the organs, but tubes inoculated -with, the blood and liver developed 
into pure cultures of the bacillus injected. 

Several white and gray mice were inoculated subcutaneously with pure cultures. 
One of the white mice died. The others remained well. 

Several efforts were made to produce the local disease by injecting pure cultures 
of this bacillus into the nasal cavity of fowls. These gave invariably negative 
results. Cultures were also fed in large quantities to several fowls without produc- 
ing the disease. 

The fact that diphtheritic lesions were not produced in fowls Avith 
this bacillus appears to be an argument against its specific relation- 
ship to the disease. Loeffler produced the disease in pigeons -with the 
bacillus he isolated In these investigations the conditions under which 
the inoculation experiments were made were presumably quite different 
from those surrounding the fowls which developed the disease. The 
variations in the degree of virulence of the organism from the different 
fowls renders it difficult to determine whether the infection depends on 
the virulence of the bacillus, or a predisposing condition on the part of 
the fowls. The etiological relation of this bacillus to the disease in 
question, however, is neither demonstrated nor affirmed, although the 
evidence in hand is quite enough to warrant the working hypothesis 
that it is, to a certain extent at least, an exciting agent in the produc- 
tion of the accompanying lesion. 

PREVENTION AND TREATMENT. 

The nature of this disease, as determined by the foregoing investiga- 
tions and the published statements of a large number of poultry raisers, 
indicates that it can be prevented, and if introduced it can be cured. 
Although it will be necessary to determine experimentally the efficiency 
of curative agents on a considerable number of fowls before formulas 
for treatment can be laid down, several important suggestions present 
themselves at this time, especially in reference to preventive measures. 

In order to prevent this disease it is evident that many conditions 
must be strictly complied with. The character of the food and the 
general sanitary conditions, including cleanliness, ventilation, and the 
temperature of the poultry houses, must be considered. Undoubtedly 
there is much to be learned in connection with the proper care of poul- 
try, especially in rural districts where it is probable that many methods 
now in use will, after a careful investigation, be found defective. Tbe 
determination of these details must necessarily be made by those 
actually engaged in the raising of poultry. In addition to the general 
sanitary methods, the following rules should be observed : 

(1) Fowls which have an exudate on any of the mucous membranes 
of the head, or which have come from flocks in which such a disease 
exists or has recently existed, should not be introduced among other 
poultry. 



PREVENTION AND TREATMENT. 59 

(2) If the disease appears in one or more fowls of a flock they should 
be immediately separated from the well ones. If possible, the source 
of the infection should be determined and removed. 

(3) The quite common practice of allowing fowls from different flocks 
to run together during the day should be discouraged. 

(4) ('are should be taken to avoid the possibility of bringing the virus 
of the disease from affected docks in the dirt or excrement which natu- 
rally adheres to the shoes in walking through an infected chicken yard. 
The same care is necessary in the interchange of working implements, 
such as shovels, hoes, etc. 

It is evident to any careful observer that the fact is too often over- 
looked that fowls, owing to their method of living, are more liable to 
infection than other farm animals. This is especially true when they 
are allowed to run at random, as they too frequently are, picking their 
living from the garbage pile and barnyards, or securing even more 
un wholesome food. There is little doubt that many so-called outbreaks 
of contagious disease among fowls are simply enzootics brought about 
by improper care. The efficiency of these few suggestions in reference 
to the prevention of this disease is demonstrated by the success of 
certain poultry raisers who adhere strictly to the teachings of sanitary 
methods. 

The wide distribution, the large number of fowls affected, and the 
usual chronic course of this disease render it oue of the few poultry 
affections for which curative measures promise to be of practical value. 
Although prevention is the safest of cures, when the disease is once 
introduced as it is in a very large number of flocks, the necessity for 
remedial treatment is apparent, and where economy is to be considered 
should be recommended. The practice sometimes followed of destroy- 
ing all of the affected birds should be discouraged. Although experi- 
ments have not been made to test the efficiency of remedies already 
recommended, or to investigate the practicability of others, the testi- 
mony of many practical poultry raisers is, as previously stated, to the 
effect that the disease is amenable to treatment. 

The most certain of the known methods of treatment is the local 
application of certain disinfectants, among which a weak solution of 
carbolic acid appears to be the most satisfactory. The fact that the 
lesions are so much exposed renders the disease especially favorable for 
topical applications. The administration of mild stimulants has also 
been recommended. In addition to the medicinal treatment, it is of 
much importance that the affected fowls be provided with proper food 
and kept in dry, warm, and well ventilated apartments. In the course 
of this study a considerable number of badly affected fowls fully 
recovered in the animal room of this laboratory with no treatment other 
than a warm, dry atmosphere. 

If the disease has reached its third stage, it is frequently necessary 
to remove the sloughed exudate, which is retained on account of the 



60 INFECTIOUS DISEASES AMONG POULTRY. 

attachment of its margins, before the application of the disinfectant. 
A few fowls have been received where it was evident that death would 
soon have followed from starvation or a closure of the respiratory pas- 
sages, and which were immediately relieved and cured by removing the 
obstructing exudate. There are certain disinfectants and stimulants 
recommended, which I am advised will give good results, if adminis- 
tered early in the course of the disease, by mixing them with the food 
and thus eliminating the necessity for individual application. 

THE RELATION OF DIPHTHERIA IN FOWLS TO PUBLIC HEALTH. 

A comparison of the bacillus of diphtheiia in man (Klebs-Loeffler) 
with the one described by Loefrler as the cause of diphtheria in fowls, 
shows that morphologically and in their pathogenesis for experimental 
animals the two organisms are in no way alike. There is also a marked 
difference in the nature of the exudates in fowls ami in man. The non- 
identity of these diseases has been clearly pointed out by Menard. 1 
Although these diseases are shown by several observations to be unlike 
in their etiology and the character of their lesions, the transmission of 
fowl diphtheria to the human species, and vice versa, is affirmed by 
several writers. 

Gerhardt 2 reports 4 cases of diphtheria among workmen who had 
charge of several thousand fowls, many of which died of diphtheria, 
in Wesselhausen, Baden. There Avere no other cases of diphtheria in 
the neighborhood, and the evidence was quite conclusive that the dis- 
ease was contracted from the affected fowls. It is also stated that an 
island on the northeastern coast of Greece had been free from diph- 
theria for at least a third of a century, when a dozen turkeys, several 
"of which were diseased, were introduced. Soon afterwards diphtheria 
appeared in a house near the garden where the turkeys were kept. 
The disease became epidemic on the island causing the death of 3G 
people, or over 40 per cent of those attacked. 

Uebrie 3 reports briefly the clinical history of G cases of diphtheria 
which occurred in the garrison of Sebdou, and states that while the 
sixth case (2 were fatal) was still under treatment in the hospital 10 
fowls kept in a house not far from the hospital were attacked with 
diphtheria, and exhibited symptoms strikingly like those present in the 
human beings. Five of the 10 fowls died, and two heads were sent to 
Arloing, who confirmed the diagnosis of fowl diphtheria. The fowls 
were fed by a hospital attendant, and it was ascertained that an identi- 
cal outbreak had occurred among the fowls at a neighboring place 
from which one of the 6 cases of human diphtheria had been brought. 
Debrie is inclined to the view that human diphtheria is transmissible 
to fowls and fowl diphtheria to man. 

1 Revue <T Hygiene, tome XII (1890), p. 410. 

2 Revue f. Thierheilkuude u. Viehzuclit, Bd. VI (1883), p. 180. 
3 Reviewediu Centralblatt f. Bakteriologie, Bd. XIII (1893), p. 730. 



CONCLUSIONS. 61 

Cole 1 reports an interesting case near Jacksonville, 111. A flock of 
fowls became affected with a disease characterized by an exudate on 
the mucosa of the head. Some of the exudates emitted a foul odor. 2 
As the weather was cold, one of the chickens was taken into the house 
where a child about 2£ years old fondled it. Four days later the child 
was taken sick apparently with diphtheria, from which it died. There 
were no other cases in the neighborhood, and the affected chicken was 
the only possible source of infection. 

The diphtheritic disease of fowls reported by Loir and Ducloux (loo. 
cit.) in Tunis, in 1894, spread to the people of that place, resulting in an 
epidemic of serious proportions. Menard refers to the fact that men 
employed to feed young squabs contracted diphtheria by blowing the 
masticated food into the mouth and crop of squabs suffering with that 
disease. Schrevens 3 reports several cases of diphtheria in children in 
which he traces the source of infection to certain poultry. 

Although the number of reported cases of the transmission of fowl 
diphtheria to the human species, and vice versa, is small in comparison 
with the extent of the disease in poultry, the evidence that such a 
transmission is x)ossible is quite sufficient to discourage the careless 
handling of diseased fowls. It is a quite common practice, especially 
in the rural districts, to bring the sick chickens into the house for treat- 
ment, Avhere the children of the household are allowed to fondle them 
at will. It is not improbable that when this disease is thoroughly 
investigated the number of cases of direct infection from this source 
will be found to be much larger than it is at present supposed. Until 
such investigations are satisfactorily completed the indiscriminate 
handling of diphtheritic chickens, especially by children, and the 
exposure of fowls to the infection of diphtheria in the human species, 
whereby they may become carriers of the virus, should be strenuously 
avoided. 

CONCLUSIONS. 

The preceding investigations, though preliminary, are important in 
bringing together certain existing facts and in a measure correlating 
certain confusing and contradictory theories in reference to a few of 
the more common so-called diseases of poultry. Although many 
important questions, especially concerning the etiology, arc as yet unsat- 
isfactorily answered, the facts elicited are of much value as a basis for 
future investigation. The definite results which have been obtained, 
and which mark the progress made in our knowledge of fowl pathology, 
may be summarized in the following determinations: 

(1) Many of the so-called diseases of fowls which are characterized 

'Archives of Pediatrics, XI (1894), p. 381. 

2 Cole's description of the disease shows that it was undoubtedly tin- same as the 
one I have studied. 

3 Bulletin de l'Acad. Koyalc de Me"d. de Belgique, VIII (1804), p. 380. 



62 INFECTIOUS DISEASES AMONG POULTRY. 

by an affection of the mucous membranes of the head, and popularly 
designated as "roup," diphtheria, influenza, and sometimes cholera, 
resemble each other so closely in their manifestations that they maybe 
considered as belonging to one and the same disease. This disease is 
distinct from the rapidly fatal malady which is better known as fowl 
cholera. 

(2) The lesions, as usually encountered, are diphtheritic in nature. 
In the advanced stages the accumulating exudates decompose and emit 
a putrid odor. In the earlier stages they are frequently of a serous or 
mucopurulent character, and not infrequently fowls die before the diph- 
theritic condition appears. 

(.'{) The same species of a pathogenic bacillus is associated with 
apparently different forms of lesions, more particularly in the serous or 
mucopurulent and diphtheritic. This bacillus is not distinguishable 
from the one described by European writers as the cause of fowl cholera 
and can not be differentiated in parallel cultures from the bacdlus of 
swine plague. It is comparable in certain respects with the supposed 
specific organisms of certain diphtheritic diseases of poultry and birds. 
Its causal relation to this disease, however, is not demonstrated. 

(4) This disease usually inns a slow, chronic course from which the 
majority of the affected fowls recover. Its long duration enables the 
lesions to be more or less modified from the effect of external contami- 
nation. Onl breaks in which the disease runs a rapidly fatal course are 
reported, but thus far they have not been encountered in the investi- 
gations of this Bureau. 

(5) This disease, or, as may subsequently be found, diseases, is ame- 
nable to treatment. The treatment consists largely in good hygiene, 
and the removal of the accumulated exudate when the disease has 
reached the advanced stage. The local application of disinfectants is 
indicated. 

(0) A large number of slight or more severe enzootics among fowls, 
due to local unsanitary conditions, are popularly considered as outbreaks 
of some contagions disease. 

(7) Judging from the results of these investigations and the recorded 
experience of certain poultry raisers, it is highly probable that this 
malady would have been prevented in a large proportion of the flocks 
in which it now exists if careful sanitary methods had been followed 
and precautions taken against the introduction of the disease through 
the purchase of affected fowls. 



A STUDY OF A BACILLUS OBTAINED FROM TIIRKE OUTBREAKS OF FOWL 

CHOLERA. 

By Veranus A. Moore. 

Although a large number of rapidly fatal outbreaks among fowls are 
reported annually from the central and southern sections of the [Tinted 
States, very little is positively known of the nature, and cause of the 
disease producing them. In 1879-80 Dr. D. E. Salmon 1 investigated 
certain epizootics among fowls in North Carolina, in which he found a 
disease comparable to the one described as cholera des poules (fowl 
cholera) in France. With the exception of his investigations, which 
were made before the development of bacteriological methods now 
considered essential and which were restricted to an inquiry into the 
nature of the disease in very few outbreaks, we have no definite knowl- 
edge of the disease known as fowl cholera in America. In Europe this 
disease has been extensively studied and the specific organism carefully 
described by several observers; the descriptions of the specific bacillus 
differ somewhat in reference to certain properties, but, without attempt- 
ing a review of the voluminous literature on the subject, suffice it to say 
that it is generally accepted that the bacillus of (owl cholera is very 
closely related to. if not identical with, the bacillus of rabbit septicae- 
mia. The results recorded by Dr. Salmon show that he obtained a 
similar organism from the fowls he examined, but unfortunately the 
condition of bacteriological science, at that time did not permit the 
determination of certain important differential biological properties. 

The further Inquiry into tin- nature and cause of this disease of fowls 
has been attended with much delay on account of the difficulty in pro- 
curing suitable material. Although this may appear paradoxical in the 
presence of so many reports of epizootics, a, moment's reflection upon 
the existing condition will reveal its truthfulness. It was shown in the 
previous article that there is a great looseness in the use, of the term 
"fowl cholera, r so that many, if not all, of the forms of local, infections, 
and contagious diseases of poultry are frequently designated by it. 
Again, there is a hesitancy among poultry raisers to report the exist- 
ence of a disease in their flocks, especially before its seriousness is 

1 Reports of the Department of Agriculture, l*s(», L882, 

63 



64 INFECTIOUS DISEASES AMONG POULTRY. 

demonstrated by the death of several individuals when it is usually 
too late for an investigation. Kepeatedly, reported epizootics have 
been visited by different investigators of this Bureau, but invariably 
the conditions found precluded the determination of the nature of the 
disease which had already run its course and disappeared. 

In the summer of 1894 three serious outbreaks of fowl cholera were 
reported, and from each of them a single fowl was received for exami- 
nation. From the organs of each of these fowls a nonmotile patho- 
genic bacillus was obtained in pure cultures. As I was unable to study 
the outbreaks in the field, the investigations here recorded are neces- 
sarily confined to the study of the organism obtained from these fowls 
and the disease produced by feeding and inoculation experiments. 
Fowls and rabbits inoculated with pure cultures of the bacillus, isolated 
from each of the affected fowls, produced similar fatal results, showing 
that very little if any difference existed in the degree of virulence pos- 
sessed by the different cultures. A comparative study of their cultural 
characters and physiological properties showed them to be identical. 
The study of this organism, however, showed that it possessed certain 
properties which have not heretofore been attributed to the bacillus of 
fowl cholera, and which are not possessed by the bacillus of swine 
plague or rabbit septicaemia, bacteria generally supposed to be iden- 
tical with it. The history of the outbreaks, so far as learned, and the 
conditions found in the fowls examined are appended: 



April 7, 1894, a dead fowl was received from Mr. S., who resides near the city of 
Washington, D. C. He had lost nearly all of his fowls (about 50) with cholera dur- 
ing the preceding few weeks, the one brought to us being tlie last to die. Me was 
requested to notify us if the disease continued in his flock, and to send all the 
fowls that were subsequently attacked. As no other fowls were received, it is pre- 
sumable that the disease had disappeared aud that the fowl examined was the last 
to be affected. 

The fowl received was a hen about 2 years old. She was in a good condition. 
The liver, spleen, kidneys, and lungs, appeared to be normal. The crop contained a 
considerable quantity of dirt, kitchen scraps, corn, and other food. In the abdomi- 
nal cavity were two large blood clots and a broken egg. The mucosa of the head 
normal Comb pale. 

Cover-glass preparations made from the liver showed no bacteria. Tubes of agar 
and bouillon were inoculated from the liver and blood. On the following day these 
contained pure cultures of a nonmotile bacillus. It was fatal to fowls, rabbits, 
guinea-pigs, and mice. 

II. 

August 8, 1894, a dead fowl was received by express from Mr. S., of Tackett's 
Mills, Va. A postal card from him bearing date of August 8, addressed to the De- 
partment of Agriculture, reads in part as follows: " I send you by Adams Express a 
hen with genuine cholera. I have lost about 80 hens and pullets in the last month." 
About three weeks later a letter was received from Mr. S. in which he stated 
that he had lost about 100 hens and pullets in the last two months from fowl cholera.. 



DESCRIPTION OF THE BACILLUS. 65 

The autopsy of the fowl received showed that death had occurred sometime before 
its arrival. The organs were somewhat discolored from post-postem changes. The 
liver was fatty, kidneys yellowish iu color, due to au excess of urates in the tubules. 
Heart muscle pale. The contents of the intestines were greenish and semiliquid 
iu consistency. Mucosa of cloaca had a yellowish color. Tubes of bouillon and agar 
were inoculated from the liver. The following day the tubes contained pure cul- 
tures of a nonmotile bacillus, which upon subsequent study was found to be identi- 
cal with the bacillus obtained from the fowl examined from the first outbreak. 

III. 

In August, 1894, while engaged in other investigations, Dr. Theobald Smith had the 
opportunity of examining a fowl which died in an outbreak of fowl cholera oil Block 
Island, R. I. The fowl died August 13. It was kept on ice until August 15, when it 
was carefully examiued. It came from a flock of about 70 fowls. The disease was 
reported to have begun in Juue, and at the time this fowl died only about 14 or 15 
were still living. The autopsy notes made by Dr. Smith show that the organs 
appeared to be normal. Four cultures were made from the spleen, liver, and blood. 
On the second day following these contained a moderately vigorous growth of anon- 
motile bacillus. 

August 31: Dr. Smith gave me these cultures for further study. They were found 
to be identical and pure. A series of inoculations and a careful study of the mor- 
phology and physiological properties of this organism showed that it was identical 
with the bacillus obtained from the other two fowls. 

Although the data concerning the nature of the disease in the three 
outbreaks is exceedingly meager, the facts iu hand are quite enough to 
show that it was practically the same in its manifestations in the three 
localities. From other sources I have learned that fowl cholera, or a 
rapidly fatal disease known as such, is not uncommon in the vicinities 
where two of tiie outbreaks occurred. No one can doubt that, if the 
history given is correct, the disease in the flocks from which the fowls 
came was of a highly contagious, or at least infectious, nature. The 
presence of the same species of a pathogenic bacillus in the organs of 
the three fowls is evidence supporting such a conclusion. As the history 
of the disease in each flock and the examination of the fowls received 
showed the absence of diphtheritic lesions, it is necessary to consider 
the disease in question either fowl cholera, in the general acceptation 
of that term, or to add a new disease to fowl pathology, which, from 
our limited knowledge of this disease in the United States, does not 
appear to be justifiable. 

DESCRIPTION OF TIIE BACILLI'S. 

Morphology. — A uonmotile, rod-shaped organism, varyiug somewhat in size accord- 
ing to the media in which it develops. In tissues of fowls or rabbits it is from 1.4 
to 1.8 n long and from 1 to 1.3 n thick. No spores or vacuoles have beeu discovered. 
The ends are rounded, so that in the shorter forms it could easily be mistaken for 
a micrococcus. In the tissues it frecpaently appears in small clumps. Involution 
forms are common. In cultures on agar it is more slender than in tissues. When 
examined in a hanging drop preparation, especially at the edge, it frequently shows 
a marked polar arrangement of the cellular protoplasm. In these preparations 
there is observed a marked dancing motion of the organisms. In old bouillon cul- 

17897— No. 8 5 



66 INFECTIOUS DISEASES AMONG POULTRY. 

tures short chains composed of hacilli united end to end are sometimes observed. 
It stains with the ordinary aniline dyes, but retains the coloring matter very feebly, 
or not at all, when treated after tbe Gram method. 

Cultural characters. — Agar. — On this medium at 37° C. the growth is moderately 
vigorous. It has a grayish, glistening appearance. Isolated colonies are from 1 
to 2 mm. in diameter, convex, with sharply defined borders. Agar plates emit a 
peculiar penetrating odor. 

Gelatin. — In this medium the growth is less vigorous. In stick cultures it is more 
abundant along the line of inoculation than on the surface. Isolated colonies are 
about 0.25 mm. in diameter, appearing as homogeneous bodies to the unaided eye, but 
slightly granular under low magnification. They have a grayish-yellow color. 

Potato. — On the surface of potatoes a delicate grayish-yellow growth appears after 
about forty-eight hours. Frequently there is no development, owing, presumably, to 
the acid reaction. 

Alkaline boullion. — In twenty-four hours alkaline bouillon becomes uniformly 
clouded. Reaction acid. The bouillon becomes clear after several days. The growth 
settles with the formation of a small quantity of friable sediment. The bacteria live 
for at least lour weeks. 

Acid bouillon. 1 — Very faintly clouded; acid reaction. Slight sediment, which is not 
viscid. 

Milk. — No change is produced in the appearance of milk for about four weeks. It 
then begins to change to a clear opalescent-appearing fluid. In about six weeks 
the milk has a decidedly opalescent appearance. Strongly alkaline in reaction. The 
addition of a few drops of acetic acid precipitates the casein. A microscopic exam- 
ination shows that the fat globules are destroyed. This condition is presumably due 
to the alkali produced by the growth ot the bacteria. This appearance of milk is not 
distinguishable from that produced by the bacillus of hog cholera. 

Fermentation of sugars. — Alkaline bouillon containing 1 per cent dextrose in fer- 
mentation tubes becomes uniformly cloudy throughout. Strongly acid in reaction. 
Similar tubes containing saccharose and lactose become clouded throughout, but they 
remain alkaline in reaction, the degree of alkalinity increasing with age. Gas is not 
produced during the growth of the bacillus in bouillon containing sugars. 

Indol and phenol. — Cultures in a peptone solution give a strong iudol reaction when 
treated after Kitasato's method. No phenol reaction could be obtained when cul- 
tures were treated according to Weyl-Lewandowski. 

Thermal death point. — Tubes of bouillon inoculated with several drops of a fresh 
bouillon culture, exposed in a water bath to a temperature of 58° C. for fifteen 
minutes or longer, did not develop. Those exposed for ten minutes or less developed 
into pure cultures of the inoculated bacillus. An exposure at 54° C. for thirty min- 
utes produced no deleterious effect. 

Effect of disinfectants. — A one per cent solution of carbolic acid was fatal in five 
minutes. A one-fourth of one per cent solution of commercial sulphuric acid de- 
stroyed life in ten minutes. Lime Avater was fatal in ten minutes, and a solution 
composed of one part lime water and three parts distilled water was equally as 
effective in one hour. Sulphur fumes were also fatal in the test applied by Dr. C. F. 
Dawson. A drop of a bouillon culture was placed upon a sterile cover-glass inside a 
large glass jar which had been specially prepared for the test. About a half tea- 
spoonful of sulphur was placed upon a sheet of asbestus and ignited. The lid of the 
jar was put on and in a short time the jar was filled with white fumes. In three 
hours time the cover-glasses were carefully removed and dropped into tubes of sterile 
bouillon. These tubes were placed in au incubator. They invariably remained 
clear. 

1 Bouillon prepared from beef without neutralizing or rendering alkaline by a 
solution of soda or potash. 



NATURE OF THE INOCULATION DISEASE. 



67 



Effect of low temperature. — Bacteria dried on cover-glasses were placed in sterile 
test tubes and exposed in a temperature of from zero to a few degrees above for 
seventeen bonis. This exposure did not appreciably retard their subsequent mul- 
tiplication in bouillon. 

The effect of drying. — This bacillus withstood drying at the ordinary temperature 
on cover-glasses for seven days. 

THE NATURE OF T1IK INOCULATION' DISEASE. 

The disease produced in the experimental animals with pure cultures of this 
bacillus is, when compared with the described effect of the bacillus of fowl cholera, 
exceedingly interesting. 

Fowls inoculated in the wing vein with 0.3 cc. of a fresh bouillon culture died in 
from three to eight days, usually on the fifth or sixth day. The temperature begins 
torise ( on the second day after inoculation. It reaches 109^ to 111° F. 1 the day before 
death occurs. In cases where the fowls live from five to six days they appear per- 
fectly well for at least three days, when the feathers begin to have a slightly ruffled 
appearance. The exposed portion of the head usually, but not invariably, becomes 
pale. Toward the last they sit in a crouched position, with the head drawn close to 
the body. They refuse food, but usually take more or less water. There is some- 
times a slight diarrhea. That portion of the excrement secreted by the kidneys 
becomes yellow. 

The changes observed at post-mortem are not conspicuous. The liver is moderately 
enlarged, soft and fatty. The spleen is occasionally enlarged. The kidneys are 
marked with yellowish lines, due to the injection of the tubules with urates. The 
intestinal mucosa is sometimes hypenernic and sprinkled with punctiform hemor- 
rhages, especially in the rectum. The contents of the intestines are, as a rule, 
greenish in color and normal in consistency. The mucosa of the cloaca is frequently 
of a yellowish color, due to urates. The heart muscle is pale. In a few cases, where 
the fowls resisted for an unusually long period, tubercle-like nodules were observed 
in the heart and lungs. 

The most marked pathological changes were found to occur in the blood. Within 
twenty four to forty-eight hours after au inoculation into the veins a diminution in 
the number of the red corpuscles and an increase in the number of leucocytes was de- 
termined. This decrease in the number of the red cells and the increase in the white 
ones continued until death occurred. This is illustrated by the notes from a somewhat 
typical case. 

Fowl No. 82. 

[Inoculated February C] 



Date. 



February 6. 
February 7. 
February 8. 
February 9. 
February 11 
February 13 
February 14 



Temper- 
ature. 
F.° 



107.4 

109 

108.2 

108. 4 

107.4 

110.2 

108 



Number of 
red cor- 
puscles. 



3, 744, 444 
3,417,391 
2, 784, 700 
2, 807, 692 
3,481,818 
2, 133, 333 
2, 530, 000 



Number of 

white cor- j 

puscles. j 



22, 222 
26, 087 
55, 000 
76, 925 
90, 909 
100, 000 
140, 000 



Remarks. 



Apparently well. 

Do. 

Do. 
Feathers ruffled: refuses food. 
Very quiet ; comb pale. 
Fowl dies later in the day. 



Unfortunately the changes produced in the blood of fowls by bacterial diseases 
are so little known that the extent to which this marked change in the blood is 
characteristic of this disease can not be determined until further investigations with 
other pathogenic bacteria are made. 

'The normal temperature of fowls, as determined by taking the temperature of 
the fowls used before inoculation, varies considerably, ranging from 104° to 108° F. 



68 INFECTIOUS DISEASES AMONG POULTRY. 

The method of destruction of the red corpuscles is not as yet satisfactorily 
explained. In his report on fowl cholera Dr. Salmon (loc. cit.) illustrated leucocytes 
surrounding the red corpuscles, but the marked diminution of the red cells was not 
determined, although he speaks of the pale color of the blood. In a few prepara- 
tions of fresh blood I have observed similar phenomenon, and also have seen portions 
of red cells within the granular leucocytes. The determination of the extent of this 
mode of destruction of the red corpuscles, however, necessitates further investiga- 
tion. It is of interest to call attention to certain other observations in connection 
with their destruction. 

In carefully heated cover-glass preparations of healthy fowl's blood stained with 
eosin and methylene blue the nuclei are colored a deep' blue, and the cellular proto- 
plasm surrounding the nucleus is stained with the eosin. In similar preparations 
made from the blood of the affected fowls there are a greater or less number of cor- 
puscles which do not take the eosin stain. In these the portion of the corpuscle 
surrounding the nucleus remains unstained or becomes slightly tinted with the blue. 
It occasionally contains one or more vacuoles, and the margin is frequently broken. 
In some instances a considerable portion of the corpuscle has disappeared. There 
are a few free nuclei. 

Fowls fed with pure cultures and w T ith the viscera of birds dying of this disease 
usually succumb in from eight to fifteen days. The subcutaneous inoculation with 
moderate quantities of pure cultures gave negative results. 

The organs and the blood of fowls dying from the inoculation disease contained 
comparatively few bacteria. This was shown in the cover-glass preparations and 
also in cultures. Frequently the inclined surface of agar rubbed with a large piece 
of the liver or spleen, or a clot of blood, contained on the following day isolated 
colonies. In sections the bacteria were frequently found lying in clumps within the 
capillaries. 

In rabbits the disease resembles very closely that produced by attenuated hog- 
cholera bacteria, although the fatal dose is much larger than for that organism. 
Subcutaneous inoculations with 0.1 to 0.2 cc. are rarely fatal. When death follows 
the lesions are characterized by slight local reactions, necrotic areas in the liver, 
enlarged and discolored spleen, and an infiltration of cells into the follicles of the 
vermiform appendix and glands about the ileo-ca^cal valve. An intravenous inocula- 
tion of 0.2 to 0.3 cc. of a fresh bouillon culture produces death in from two to three 
days. In these cases the spleen is engorged with blood, the liver swollen, and the 
intestinal mucosa contains hemorrhagic areas. A larger dose produces death in from 
eighteen to twenty-four hours. An intravenous injection of a small quantity of 
culture produces lesions similar to those following the subcutaneous inoculation. 
Cover-glass preparations from the liver, spleen, and blood made soon after death 
show few elongated bacteria. If a rabbit is allowed to lie for twenty-four hours 
after death cover-glass preparations show innumerable oval bacteria, which usually 
exhibit a polar stain. 

A guinea-pig inoculated in the abdominal cavity with 0.2 cc. of a bouillon cul- 
ture died in seven days. The autopsy showed about 50 cc. of a clear, lemon-colored 
serum in the abdominal cavity. The viscera were covered with a grayish membra- 
nous exudate. The pleural cavity contained a large quantity of serum. Lungs 
collapsed. Subcutaneous inoculations of 0.5 cc. proved fatal in from six to eight 
days. There was a purulent infiltration into the subcutis about the point of inocu- 
lation. Spleen enlarged, dark colored, and friable. Liver pale and usually fatty. No 
intestinal lesions. Comparatively few bacteria in the organs as shown in cover- 
glass preparations. 

White and gray mice inoculated subcutaneously with 1 to 2 drops of bouillon 
culture died in from three to five days. The only pronounced macroscopic lesion 
observed was an enlarged and discolored spleen. Mice inoculated similarly with a 
much smaller quantity (a single small loop of culture) remained well. 



NATURE OF THE INOCULATION DISEASE. 69 

It was thought that perhaps the bacillus was attenuated because the 
fowls were among the last to die in their respective outbreaks. On that 
account several series of inoculations were made in different animals 
for the purpose of increasing its virulence, the culture from the fowl iri 
the first outbreak being used. These gave negative results. Several 
other experiments are now in progress for the purpose of accelerating- 
its pathogenesis. It seems, however, that its virulence is not easily 
changed by any of the ordinary methods. After nearl}- a year's pres- 
ervation in subculture it is as rapidly fatal as when first isolated. 

The bacillus here described differs from the description of the bacil- 
lus of fowl cholera (rabbit septicaemia or swine plague) in the following 
particulars: 

(1) Morphology. 
2 Its effect upon milk. 

(3) Its effect upon sugars. 

(I) Its degree of virulence for rabbits and fowls. 

(.5) The nature of the inoculation disease, especially in rabbits. 

The morphological changes consist in a slight increase in size and 
the feebleness with which it takes the polar stain. The fact is inter- 
esting, however, that the polar stain is well marked when the bacillus 
is allowed to multiply in the dead animal body. 

The saponification of milk is very marked. This property belongs to 
the hog-cholera group of bacteria, and it has not occurred in parallel 
cultures of the swine-plague bacillus or other members of that group, 
in which it is generally conceded by authorities in bacteriology the 
fowl-cholera bacillus belongs. 

The bacilli of rabbit septicaemia and swine plague produce acids in 
bouillon containing dextrose and saccharose, while this bacillus changes 
dextrose only. I have not had an opportunity of studying the bacillus 
of the European disease, and consequently this variation is assumed on 
the authority of the statements that these species are identical. 

Thevirulenceof this bacillus is much less than that ordinarily recorded 
for fowl cholera. Dr. Salmon produced fatal results in fowls by the 
subcutaneous injection of minute quantities of a pure culture, while 
this organism requires for fatal results an intravenous injection of a 
much larger amount. In rabbits the dissimilarity is much greater. 
The bacillus of fowl cholera is said to destroy rabbits with acute septi- 
caemia within twenty-four hours after a subcutaneous inoculation with 
small quantities of pure culture, but this organism produces a disease 
characterized by certain definite anatomical changes. 

The theory that possibly the variation in the lesions is due to an 
attenuation of the bacillus or a resistance on the part of the animal 
docs not hold, as the disease produced in rabbits with this organism is 
different from that obtained with attenuated rabbit septicaemia bacteria. 
It has frequently been pointed out in the publications from this labora- 
tory that attenuated rabbit-septicaemia or swine-plague bacteria pro- 



70 INFECTIOUS DISEASES AMONG POULTRY. 

duce local infiltrations and an inflammation followed by an exudate on 
one or more of tlie serous membranes. 

Another point of difference, taking the bacillus of fowl cholera to be 
identical with that of swine plague, is the inability to render rabbits 
immune to the disease by previous injections of sterilized cultures. 
A carefully conducted experiment was made in which 10 cc. of steril- 
ized bouillon culture was injected intravenously in repeated small 
doses in two rabbits. They were subsequently inoculated with a mini- 
mum fatal dose of pure culture. They died with the control rabbits. 
Such negative results are invariably obtained with hog-cholera bacteria, 
but many experiments with swine-plague bacteria show that such treat- 
ment will quite as surely produce a pronounced resistance to that disease. 1 

There are, however, certain similarities in the disease produced in 
fowls with the one studied by Dr. Salmon in his investigations in North. 
Carolina. These are, lor the greater part, the rise in temperature, the 
period of incubation, yellowish color of the urates, paleness of the 
comb, and the refusal of food. The gross pathological changes are 
also comparable. The diarrhea was less marked in the disease I have 
produced. 

The study of this organism and its pathogenesis are as yet too 
incomplete to admit of further comparisons at this time. The fact has 
been shown that in the inoculation disease there is slight or no diar- 
rhea, and pronounced pathological changes occur in the blood. Should 
these conditions be found to exist in the disease as it occurs in epi- 
zootics it is evident that the term fowl cholera is an unfortunate one. 
It has further been pointed out that the bacillus obtained from three 
outbreaks of reported fowl cholera differs materially from the organ- 
ism generally accepted, and ofttimes described by European investiga- 
tors as the specific cause of that disease. It is quite possible that 
there are several varieties of fowl cholera, and that the bacillus here 
described is the etiological factor of one of these forms. The extent 
to which this bacillus is distributed in this country as the cause of epi- 
zootics among fowls can not be determined until further investigations 
are made. 

1 Bulletin No. (j of the Bureau of Animal luuuetry, 1894, p. ti5. 



ON A PATHOGENIC BACILLUS OF THE HOG-CHOLERA GROUP ASSOCIATED WITH 
A FATAL DISEASE IN PIGEONS. 

By Veranus A. Moore. 
HISTORY OF THE DISEASE. 

In July, 1894, an investigation was made into the nature of a reported 
epizootic among pigeons at Vineland, jST. J. The disease was found, 
however, to be restricted to the cotes belonging to Air. A. II. Ilawley, 
and while it was said to be very destructive, its course was slow, and 
the heavy loss which it occasioned was due to its continued existence 
and spread. The only symptom observed was a general emaciation, 
or "going light," as expressed by pigeon fanciers. He had examined 
post-mortem a large number of the birds, but the only apparent patho- 
logical change noticed, other than the loss of flesh, was an exceed- 
ingly pale heart muscle. 

In addition to the affection mentioned, a few pigeons had died from 
a disease known as " megrims," which is characterized by emaciation 
and a peculiar turning of the head from one side to the other, witli 
occasional paroxysms of flying about, apparently in an aimless man- 
ner. The economic importance of this disease, however, was said to be 
insignificant, and it is considered here in connection with the more 
serious affection on account of the identity of the bacilli isolated from 
the diseased pigeons. 

At the time of my visit Mr. Ilawley had a pigeon in the advanced 
stage of each of these apparently different diseases, and several 
others which he said showed beginning symptoms. As these diseases 
appeared to have followed outbreaks of a rapidly fatal affection which 
had occurred at variable intervals among his pigeons during the pre- 
ceding few years, a brief historical sketch of the disease in his cotes is 
of special interest. 

Mr. Ilawley stated that be began to raise pigeons early in 1889. At 
first he kept about 160 pairs. For nearly three years his pigeons 
remained well. Late in the fall of 1891 he purchased 50 pairs, aged 
about 10 months, from the Fanciers 7 Pigeon Club, of Philadelphia. 
About four weeks later these pigeons began to die from a disease des 

71 



72 INFECTIOUS DISEASES AMONG POULTKY. 

ignated by him as cholera. About one-half of the purchased pigeons 
died. The disease did not spread to the pigeons formerly kept on the 
place. A second and more destructive outbreak occurred in the 
spring of 1892. During the summer two other quite severe outbreaks 
occurred. In August, 1893, he lost 125 birds from the same cause. At 
this time the disease was unusually rapid in its course, the pigeons 
being sick for only twelve to fourteen hours. The cotes in which the 
disease occurred were thoroughly sprayed with kerosene emulsion and 
the floors were washed with carbolic acid. They were vacated and left 
unoccupied until the spring of 1894, when 75 pairs of pigeons, selected 
from the other cotes, were placed in three of the apartments, 25 in each, 
and 17 pairs were purchased and put in a fourth apartment of the same 
house. The four apartments were arranged side by side, occupying the 
entire building. The pigeons remained well for about a month, when 
cholera broke out in two (first and third) of the apartments. About 15 
birds died, when the disease was checked by the use of medicines. 

Soon after the first outbreak of so-called cholera, late in 1891, pigeons 
began to die of the disease under investigation. The number of deaths 
continued to increase until the profit of the business was consumed and 
the extermination of the pigeons threatened. A record of the mortality 
kept during the first few months of 1891 showed that in February 83, 
in March 36, and in April GO deaths occurred. In May and June the 
loss was about the same. In July a much smaller proportional number 
had died up to the time of the investigation. The prevalence of the 
disease among young pigeons was noted by Mr. Hawley, although old 
birds were occasionally affected. All of the affected pigeons were 
examined. 

Pigeon No. 1. — This pigeon was found dead on the morning of July 19. It was 
about 6 weeks old. There was evidence of a slight diarrhea. It was much emaciated. 
The mucosa of the eyes, nares, and mouth was normal. The liver had a peculiar 
greenish color, due, presumably, to post-mortem changes. The kidneys were of a 
pale yellowish color. Intestinal mucosa normal. The heart muscle was exceedingly 
pale, fatty. Tubes of agar were iuoculated from the liver and blood. These con- 
tained on the day following pure cultures of a motile bacillus belonging to the hog- 
cholera group, as will be shown in its subsequent description. 

Pigeon No. 2. — This was an old pigeon. It had been sick for several days. It 
turned its head continually from one side to the other and walked with difficulty. 
The left eye was closed and contained a small quantity of mucus. It was killed for 
examination. Pigeon much emaciated. No lesions were fouud in thoracic or abdom- 
inal organs. In the subarchnoid space over the cerebellum and the posterior lobes of 
the cerebrum there was a grayish-yellow, friable exudate one-half to 1 mm. in thick- 
ness and easily removed. Subjacent brain tissue reddened; otherwise normal in 
appearance. The dura appeared to be normal. The exudate was composed for the 
greater part of degenerating cells and bacteria. Tubes of agar were inoculated from 
the exudate over the brain and from the heart blood. The latter remained clear; 
the former developed into pure cultures of a bacillus not distinguisbable in its bio- 
logical character from the one obtained from the organs of pigeon No. 1. 

All of the suspected pigeons were killed and examined, but in every case the organs 
appeared to be normal and the culture media inoculated remained clear. 



DESCRIPTION OF THE BACILLUS. 73 

DESCRIPTION OF THE BACILLUS. 

Morphology. — An actively motile bacillus, varying in size from 1 to 1.6// in length 
and about 1 fx in width. The size varies appreciably in different media. No spores 
have been detected. The ends are rounded in cultures, but in tissue they appear to 
be more pointed. In preparations from tissues it usually appears in pairs, united 
end to end. Frequently, however, it is observed in clumps. Tbe rlagella are easily 
demonstrated by Loeffler's process. The number of filaments vary, eight being the 
maximum number observed in a single bacillus. In preparations from tissue it 
usually exhibits a light center with a uuiformly stained periphery. In preparations 
from cultures it usually shows very little, if any, unstained area. It does not take 
the Gram stain. 

Cultural characters. — Agar. — On the inclined surface of this medium after twenty- 
four hours at 37° C. a grayish, glistening, nonviscid growth appears. When isolated 
the colonies are convex, 0.5 to 1.5 mm. in diameter. Edges sharply defined. The 
growth is increased slightly during the next twenty-four hours. In stick cultures 
there ic a grayish growth along tbe course of the needle track. 

Gelatin. — In this medium the growth is not vigorous. Surface colonies appear as 
small grayish dots. When magnified they are finely granular in appearance and of 
a yellowish tint. In older colonies there is a distinct band which is less granular 
in appearance about the circumference. It is not liquified. 

Potato. — It forms on potato a thin, glistening growth, having a faintly yellowish 
color. When the reaction of the potato is very acid no growth appears. 

Alkaline bouillon. — This medium becomes uniformly clouded after twenty-four 
hours. The reaction is faintly acid, owing to the fermentation of the muscle sugar. 
After a longer growth a thin, grayish membrane forms over the surface of the liquid 
and a grayish band frequently appears on the sides of the tube at the surface of the 
liquid. The reaction becomes strongly alkaline in old cultures. In acid bouillon the 
growth is feeble and the reaction is not appreciably changed. 

Milk. — When this medium is faintly acid in the beginning it slowly becomes alka- 
line. In about three weeks it gradually changes to a clear, opalescent fluid, clue, 
presumably, to the alkali 1 produced by the growth of the bacteria, as the milk at 
this time is very strongly alkaline. The addition of a few drops of acetic acid pre- 
cipitates the casein. If the culture is allowed to remain in the thermostat for sev- 
eral weeks the volume of the milk shrinks, due to evaporation, and the remainiug 
part becomes viscid and of a light brownish color. 

Alkaline bouillon containing dextrose. — In this medium it produces a marked fer- 
mentation of thi' sugar with the formation of gas. The acid resulting from the fer- 
mentation gives the fluid a strong acid reaction. The gas produced (when collected) 
in the fermentation tube replaced 54.8 per cent of the liquid in the closed branch. 
The gas contained 35.7 percent C<) : (gas absorbed by potassium hydrate) and 64.3 
per cent H (explosive gas). 

In similar bouillon containing lactose and saccharose the liquid became uniformly 
clouded throughout both branches of the tube. No gas was formed. The reaction 
remained alkaline, and after some days the degree of alkalinity, as detected by litmus 
paper, was much increased. 

A marked indol reaction was determined by Kitasato's method. 3 

Thermal death point. — This organism is destroyed in cultures by an exposure of ten 

1 It was shown in Bulletin No. 3, 1893, p. 43, that the addition of a few drops of a 
strong solution of caustic potash or soda would produce this appearance in milk. 

: This consists in cultivating the bacillus at 37° C. in a sterilized solution composed 
of 1 per cent peptone and 0.5 per cent sodium chloride in distilled water for from 
one to three days. To these cultures 1 cc. of a 0.02 per cent solution of potassium 
nitrate, freshly prepared, and about 3 drops of chemically pure sulphuric acid are 
added; a violet-pink color indicates the presence of indol. 



74 INFECTIOUS DISEASES AMONG POULTRY. 

minutes to a temperature of 58° C. in a water bath. It resisted drying on cover- 
glass preparations made from bouillon cultures at the temperature of the room for 
eight days. Similar tests were not made with preparations made directly from the 
organs of animals. 

Disinfectants. — The effect of lime and carbolic acid upon this organism shows that 
a solution of lime weaker than lime water is not effective, and that a 2 per cent solu- 
tion of carbolic acid requires one hour to destroy life. 

Pathogenesis. — Rabbits inoculated in the ear vein with 0.3 cc. of bouillon culture 
died in thirty-six to forty-eight hours. There was a general congestion of the inter- 
nal organs. The intestinal mucosa was especially reddened in certain areas. A sub- 
cutaneous injection of a similar quantity of culture produced death in from four to 
six days. In these cases there was considerable purulent infiltration into the sub- 
cutaneous tissue about the place of inoculation. The liver was sprinkled with 
necrotic areas and the spleen much enlarged, dark colored, and friable. When a 
smaller quantity of culture was iujected the local lesion was much more severe, and 
the follicles of the vermiform appendix and also certain of those of Peyer's patches 
were infiltrated with cells, giving them the appearance of round, whitish dots. 
White mice died in from three to six days after a subcutaneous inoculatiou with one 
to three drops of bouillon culture. The only lesion observable was an enlarged and 
discolored spleen. Guinea-pigs died in from five to ten days after subcutaneous inoc- 
ulations with from 0.1 to 0.2 cc. of a fresh bouillon culture. Pigeons resisted a sub- 
cutaneous inoculatiou with a small dose, but a larger quantity (0.2 to 0.5 cc.) 
injected into the circulation or pectoral muscle produced death in from two to eight 
days. 

Two pigs inoculated with 5 cc. each of a bouillon culture, oue subcutaneously 
and one in the femoral vein, remained apparently well. 

The description of this bacillus shows that it undoubtedly belongs to 
the hog-cholera group of bacteria, although it differs in certain impor- 
tant properties from the specific bacillus ordinarily encountered in 
destructive outbreaks of hog cholera. As several varieties ' of the hog- 
cholera bacillus have already been described, it is important to note the 
specific variations of the bacillus in question from the virulent form 
described 2 originally and the one which is generally meant when this 
organism is mentioned. The differences are as follows: 

(1) It is appreciably larger. 

(2) In bouillon a delicate membrane appears on the surface of the 
liquid and in old cultures a deposit is formed on the sides of the tube. 

(3) There is a marked indol reaction. 

(4) It is less rapidly fatal in small doses for experimental animals, 
and the lesions produced in rabbits are comparable to those follow- 
ing the inoculation with ihe more attenuated varieties. The negative 
results from the pig inoculations are parallel with many similar ones 
heretofore made with the virulent variety. 

■In Bulletin No. 6 of the Bureau of Animal Industry, 1894, Dr. Theobald Smith 
has pointed out the difference that exists in the morphology, cultural characters, and 
pathogenesis of the hog-cholera bacillus as encountered in different outbreaks of 
that disease. He also found that several bacilli associated with diseases other than 
hog cholera belong to the same group. These are a bacillus found by himself in a 
mare after abortion, Bacillus enteriditis, and Bacillus typhi murium. 

2 Second Annual Report of the Bureau of Animal Industry (1885), p. 212. It was 
called at that time swine-plague bacterium. 



DESCRIPTION OF THE BACILLUS. 75 

(5) It is slightly more resistant to the action of certain disinfectants. 

The variations, with one exception, have already been noted in some 
one or other of the varieties described by Dr. Smith. It is of interest 
to note that of the seven varieties of hog-cholera bacillus which he 
has pointed out the indol reaction was markedly present in but one 
variety (Bacillus cholerw suis ?-), and that a nonvirulent form. This is 
of interest, especially as the indol reaction is prominent in the colon 
group of bacteria. The greater resistance to disinfectants is also inter- 
esting. 

The discovery of this bacillus in a disease of pigeons is of much 
interest in the accumulation of data concerning the distribution of this 
organism and the range of its disease-producing power. The source of 
infection is somewhat obscure, but the history points very clearly to its 
introduction with the pigeons purchased in Philadelphia. Accepting 
that as the source of infection, it. is presumable that the acute disease 
breaking out at variable intervals was due to this organism, which for 
undetermined reasons became increased in virulence, or on account of 
certain conditions the pigeons were rendered more susceptible to it. A 
careful inquiry failed to reveal the existence of outbreaks of hog cholera 
in Vineland for many years. It was also learned that the disease found 
among Mr. Hawley's pigeons had not appeared in other cotes in that 
vicinity. 

The conditions under which the affected pigeons were kept and the 
care exercised in their management seemed to be all that could be 
desired. The cotes, however, were located in a slight depression, the 
land surrounding them being appreciably higher, so that drainage is 
imperfect. The soil is quite sandy, however, and dries quickly after 
rains. 

The fact was elicited in conversation with a number of pigeon raisers 
in southern JSTew Jersey that a rapidly fatal disease, comparable to the 
one described by Mr. Hawley, does occasionally occur among pigeons 
where the source of infection can not be explained. I was unable to 
find such an outbreak, although one gentleman told me of recently 
losing 1,500 birds in one of these outbreaks. The results of the inves- 
tigation at Vineland render a careful study of the so-called pigeon 
cholera of much interest. It is not improbable that future inquiry will 
find that these outbreaks are due to bacteria belonging to the hog- 
cholera group. 

The appearance of this bacillus in the brain of the pigeon affected 
with the so-called "megrims'' is of special interest. It was stated by 
Mr. Hawley that the old birds were affected in this way. This disease 
is reported by pigeon raisers to be invariably fatal and more or less 
common, although comparatively few birds are affected. In this case, 
however, it appears that the disease was etiologically the same as that 
which caused the large number of deaths among the younger pigeons, 
the lesions being localized on the brain. This fact renders the further 



76 INFECTIOUS DISEASES AMONG POULTRY. 

investigation of "megrims" important in order to determine whether 
the single case here reported is comparable in its etiology to the dis- 
ease generally The symptoms appear to be characteristic, so that the 
disease is readily recognized by pigeon fanciers. 

The fact tliat pigeons, which are ordinarily quite refractory to hog- 
cholera bacteria, should be affected with a disease due apparently to 
an organism belonging to that group of bacteria is of much importance. 
Although it has been shown that several varieties of the bacillus 
described originally from outbreaks of hog cholera are associated with 
other diseases and in different species of animals, tbey appear not to 
have heretofore been encountered as the apparent cause of any disease 
in pigeons or other birds, with the possible exception of the bacillus 
described by Loeffler as the cause of pigeon diphtheria. 

The importance of the results of this investigation, which was 
materially restricted by the limited number of examinations possible, 
is centered in a few determinations in reference to the hog-cholera 
bacillus. 

(1) The discovery of a member of the hog-cholera group of bacteria 
apparently as the etiological factor in a chronic disease of pigeons. 

(2) The appearance in pure culture of a variety of the hog-cholera 
bacillus from the exudate covering a portion of the brain of a pigeon 
killed in the last stages of the disease popularly known as "megrims." 

(3) The presence of a marked indol reaction in cultures of a decidedly 
pathogenic bacillus of the hog-cholera group. 

(4) The discovery of a variety of the hog-cholera bacillus in which 
the cultural characters and the physiological property of producing 
indol tend to assimilate to a marked degree those of closely related 
saprophytic forms, but which in its pathogenesis for experimental 
animals falls but little below that of the virulent form originally 
described. This striking commingling of saprophytic tendencies and 
highly parasitic powers tends to strengthen the proposed theory that 
the hog-cholera bacillus is derived from the closely related colon group 
of bacteria. 



DESCRIPTION OF PLATE I. 

Fig. 1. Cseca of turkey No. 5 (somewhat reduced). Both are distended and filled 
with exudate. They are unusually short. (See tig. 2 on PI. II.) 

FlG. 2. Liver of turkey No. 26 (dorsal aspect). Reduced to seven-ninths of original. 
The circular spots which are seen on the surface are shown in color in fig. 
1 on PI. III. The other surfaces of this liver presented a similar appear- 
ance. The liver is considerably larger than in health. 
78 



Bul. 8, Bureau of Animal Industry 



Plate I 




A. HOEN & CO. 



DESCRIPTION OF PLATE II. 

Fig. 1. Caeca of a healtby turkey, probably 9 months old. The central tube is the 
small intestine, the food passing downward in the direction of the arrow. 
Below, at the junction of the cteca with the intestine, the food is drawn 
into the ca;ca by suction. 

Fig. 2. One csecum of turkey No. 5 (see fig. 1, PI. I), cut open longitudinally. The 
middle portion of the tube is greatly distended and occluded with an 
exudate which is firm in consistency. The upper portion contains small 
stones which have passed down from the gizzard. The irregular thicken- 
ing of the wall of the tube is shown by a faint line bordering the exudate. 

Fig. 3. The other csecuin of No. 5, cut transversely. The great thickening of the 
wall is shown, together with the presence of a loose plug within the tube, 
consisting of a firm exudate. Both this and the preceding figure were 
drawn from the alcoholic preparation. (Natural size.) 

Fig. 4. One ca?cuin of turkey No. 23, slit open and the mucous membrane exposed. 
The wall of this organ is very much thickened, as may be easily seen by 
comparing with the healthy tube of a turkey fully six months older (in 
fig. 1). On the mucous membrane are masses of exudate firmly attached to 
certain spots of increased thickness. (From an alcoholic preparation.) 

Fig. 5. Spots on the liver of turkey No. 34 (natural size). Drawn from aiv alcoholic 
preparation. 
80 



Bul. 8, Bureau of Animal industry 



Plate II 



Fig. IV 





Fiq. II 





Fig. Ill 




I : % 



- — i 



A. HOEN & CO. 



17897— No. 8 C 



DESCRIPTION OF PLATE III. 

Figs. 1 and 2. Spots on the liver of turkey No. 5. (See photographic reproduction, 
fig. 2 of PI. I.) The spots are showu both isolated and confluent. The 
reticulated structure of these spots is better brought out in the photograph 
referred to. 

Fig. 3. Left lobe of liver of turkey No. 52 (convex surface). The large yellow area 
in the upper portion of the figure represents a mass of dead tissue pene- 
trating nearly through the entire thickness of the liver. On the right the 
pale grayish spot represents diseased liver tissue which is undergoing 
repair. Similarly, the spots in the lower portion of the figure correspond 
to diseased regions partly healed. Several other spots readily detected in 
the specimen could not be clearly brought out in the figure. The diffuse 
change, probably reparative, is shown along the lower margin. 
82 



Bul. 8, Bureau of Animal Industry. 



Plate III 




A. HOEN & CO. 



DESCRIPTION OF PLATE IV. 

Fig. 1 (X500). A -portion of the mucous membrane of a caecum of turkey No. 26, 
cut transversely. The tissue was hardened in corrosive sublimate aud alco- 
hol, cut dry after embedding in paraffin, and stained in Delafield's hema- 
toxylin and in eosin. 
(a) Nuclei of the epithelium of a crypt or tnbule struck nearly tangeutially 
by the section. 

(a) Mucin cell represented by a cavity in the section. 

(b) Spindle-shaped cells belonging to the reticulum of the tissue between the 

tubules. 

(c) Protozoa, single and in compact groups, situated within the meshes of the 

reticulum. 

(d) Multinucleated (giant) cell which lias enveloped some of the protozoa. 
Fig. 2 ( X500). From the same section. 

(a) A large group of parasites inclosed in a space of the mucous membrane. 
(a') Single parasite. 

(b) A tissue cell in process of division. 

Fig. 3. Section of the liver of turkey No. 34. Hardened in alcohol, cut dry in 
paraffin, and stained in hematoxylin and in eosin. A large collection of 
protozoa {a) occupying the space formerly occupied by the liver cells. 
They are probably somewhat forced apart by artificial pressure, for in 
other sections of the same liver compact masses of protozoa of equal size 
were not infrequently seen. The parasites are surrounded by capillaries 

(b) dilated and filled with red corpuscles; (c) round cells or leucocytes. 
Fig. 4 (X500). From the same section as fig. 3. Protoza (a) embedded in a granular 

matrix containing a few nuclei. Some of them largely disintegrated (b). 

(c) A capillary filled with red corpuscles. The matrix resembles the pro- 
toplasm of the liver cells. 

84 



Bul. 8, Bureau of Animal Industry. 



Plate IV 





Fiq. IV 




A. HOEN & CO. 



DESCRIPTION OF PLATE V. 

Fig. 1. The protozoan parasites as they appear in crushed and teased fresh tissue 
(X 1,000). 

Fig. 2. A parasite with granular body to which a fragment of a giant cell still 
adheres. The bodies in this fragment are fat globules (x 1,000). 

Fig. 3. Section through the liver of No. 9. Hardened in alcohol and stained in 
hematoxylin and eosiu ( X260). A group of indistinctly demarcated giant 
cells containing a considerable number of vacuoles which indicate the 
position of inclosed microparasites. This group of giant cells is situated 
within what appears to be a thrombosed blood vessel. The coats of the 
vessel are faintly traceable. The surrounding tissue is involved in coagu- 
lation necrosis, presents a homogeneous appearance, and contains scattering 
nuclei. 

Fig. 4 (X500). A giant cell over 80 /i in diameter among a group of ten or more 
slightly smaller ones found in the wall of cascuin of turkey No. 1. The 
mucous membrane had ulcerated away, and the greatly thickened remain- 
der (3 to 4 mm. thick) was completely infiltrated with round cells, (a) Pro- 
tozoa, two of them within the cell. 

Fig. 5 (X500). Transverse section through a crypt or tubule of the diseased crecum 
of turkey No. 26. The lumen of the tubule is packed with minute bodies, 
probably flagellates, (a) Vacuole-like spots representing mucin cells. 
(b) Mitosis. 

Fig. 6 (x500). Blood from healthy turkey No. 12, dried as a thin film on a cover- 
glass and stained, after being fixed at 120° C, in Ehrlich's hematoxylin. 
(«■) Red corpuscles, (b) leucocytes, (c) flagellates, very much broadened 
in appearance by the drying process. 

Fig. 7 (X500). Flagellate as seen in the fresh blood of healthy turkey No. 33. 
86 



Bul. 8, Bureau of Animal Industry 



Fiq, I 







Fig. II 




B w Ml 








Fig. VII 



Fig. V 




Fig. VI 
Q b 







A. HOEN & CO. 



LBFe '07 



DESCRIPTION OF PLATE VI. 

Fig. 1. The roof of the mouth of fowl No. 73, showing the position of the exudate. 

(Natural size.) 
Fig. 2. The floor of the mouth, showing the exudate over the tongue. (Natural 

size.) 
Fig. 3. Section of exudate with subjacent tissues, from mouth of fowl No. 59, showing 

destruction of the epithelium and cell infiltration of the underlying 

tissue (Xl7). 
Fig. 4. Sections of the cornea of fowl No. 65 after the removal of the mass of 

sloughed exudate (Xl7). 



Bul. 8, Bureau of Animal Industry 



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HAINES, DEL. 



A. HOEN & CO. 



INDEX 



Page. 

Amoebic dysentery jg 19 

Amoeba meleagridis, appearance in giant cells 19 

tissue 17 

effect of staining reagents 17 

fate 19 

in connective tissue spaces 18 

is it an intracellular parasite? 19 

multiplication 19 

nature 18 

notes 15 

Animals, inoculation with exudate of fowls affected with diphtheria 55 

Bacillus coli communis 23, 43, 47, 49 

description of variety 43 

enieridiiis 74 

typhi murium 74 

Blackhead. (See Protozoan disease of turkeys.) 

Caeca, affections 9 

Carbolic acid 59 

Chloride of lime 26 

Cholera des }>oules. (See Fowl cholera. ) 

Coccidium ovi forme 9 

tenellum 9 

Coops, disinfection 26 

Corrosive sublimate 26 

Councilman and Lafleur, investigations 20 

Cover-glass preparations 54 

Cushman, S., assistance 7 

Dawson, C. F 22, 57, 66, 73 

Diphtheria in fowls 39 

conditions favorable 40 

contagiousness 40 

economic importance 40 

epizootics 41 

lesions 51, 52 

methods of investigation 11 

outbreaks investigated 42, 46, 49, 50 

pathogenic bacillus associated with the lesions 42, 

44, 45,47,48,49,53,55. 5ti 

prevention and treatment 58 

relation to public health 60 

saprophytic bacteria associated with 53 

symptoms 40 

Disease in pigeons 71 

description of bacillus associated with 73 

relation to Bacillus cholera; suis 73 

economic importance 72 

history • 71 

symptoms 71 

Epithelium, destruction 10 

89 



7+ 



90 INDEX. 

Flagellate 21 

Flagg, Professor, assistance 7 

Fowl cholera 63 

nature of inoculation disease 67 

outbreaks 64, 65 

pathogenic bacillus obtained from fowls 65 

its relation to rabbit septicaemia and swine- 
plague bacilli 65, 69 

Gallua domeslicus 42 

Giant cells, appearance of parasites 17 

Hawley, A. H., experiments in raising pigeons 71 

Kilborue, F. L., examination of fowls 45 

Kruse and Pasquale, investigations 20 

Leucocy tosis 14, 67, 68 

Megrims in pigeons 71, 75 

Microparasites. (See Ainoeba meleagridis.) 

Molluscum contagio8um 18 

Nonmotile bacillus in diphtheritic lesions of fowls. (See Diphtheria.) 

etiological relation to the disease 58 

Mitoses 10 

Pathogenic bacillus of the hog-cholera group. (See Disease in pigeons.) 

Pigeons, diseases, notes 71, 72, 73 

Protozoan disease of turkey 7 

analogy to amoebic dysentery 10 

appearance of liver 11 

changes of the liver 12 

extent of ca?cal disease 16 

liver disease 16 

external appearance . r ■- 8 

giant cells 11, 13 

parasites in the liver 13 

multiplication 13 

relation of bacteria 11, 21 

to certain other diseases of poultry 22 

diseases of cseca in fowls 26 

other ca?ea disease in turkeys 22 

seat of disease 9 

special characters 8 

symptoms 8 

treatment 26 

von Ratz, S., investigations 23 

Rhode Island Station - 7 

Roup. (See Diphtheria. ) 

Salmon, D. E., results of investigations 63,68 

Schroeder, E. C, experiments 46 

Slaked lime . .' 27 

Taeniasis in fowls 46 

Toxic substance 51 

Traumatism 41 

Turkeys, diseases of. (See Protozoan disease. ) 

examination, history 27 

tapeworms in 8 

voluntary contributions 7 

Vineland, N. J., epizootic diseases among pigeons 71 

Warts 18 

Wheeler, Professor, acknowledgments 7 















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